Architecture of mobile applications and wireframes

Introduction

Once the foundations of user-centered design and their application in the design of interfaces for mobile devices, and as a continuation in the process of development of an application or interactive product, in this second module we are going to work on how that users will be able to access the information, content or services that we want them to receive offer. Specifically, we will study strategies to design the information architecture of our product and we will begin to “shape” it using rapid prototyping techniques. And as in the module above, we will do so always taking into account the needs and objectives of our users.

Objectives

The objectives that the student must achieve with the study of this module are:
  1. Know what information architecture is and its relationship with the experience of user.

  2. Know techniques to classify and represent information, as well as to structure navigation in our application.

  3. Understand what interaction design is.

  4. Review the principles that inspire the design of mobile applications.

  5. Know rapid prototyping techniques for our ideas and their usefulness within the design process.

1.Information architecture

According to Rosenfeld and Morville, pioneers of the discipline, the architecture of the information:
  • Clarifies the mission and vision of the product.

  • Determine what contents and functionalities will have the place.

  • Indicates how users will find information by defining of systems organization, navigation, labeling and search of it.

  • Projects the way the site will be will adapt to change and growth with him passage of time.

In short, information architects help the user to find and manage information effectively. We find information architecture in web pages, in the design of mobile application interfaces and software in general, all types of gadgets, dispensing machines, even in printed material.
Although for most users "the interface is the application", we must understand information architecture as a discipline closely related to the user experience, since the usability of the application will not depend only on the design of the interface, but also the structure and organization of the information it contains, or in other In other words, the “non-visible component of the design” (Hassan and Martín, 2004).
Information architecture is, therefore, responsible for influencing the following aspects:
  • How is it going to classify information. In the first phase, the architect of information will have to analyze all the available information and determine to what degree it is can be broken down into smaller units, but fully endowed with meaning.

  • How is it going to be navigation structure, the hierarchy between content and the relationship between information nodes.

  • How are they going to label the different options available.

  • How is it going to be search system.

Once again, we will put the user at the center of this process and We will design the architecture of our application taking into account at all times who is our audience and what are their objectives, as well as the context of use of our application, since they will determine the way in which we will organize and display the contents.

1.1.Classification of the information

There are some techniques to work on the architecture of the information from our application adapting to the mental model of the users. We examine them continuation.
1.1.1.Inventory of contents
Using this technique we proceed to identify all the "pieces of the “puzzle” that we are going to build. Normally, we will do this by listing each and every one of the sections (or screens) that our application will need. It is advisable to be as detailed as possible possible, without worrying at this point about grouping the contents according to categories –non-existent yet, since we have not yet decided on them– or to their characteristics.
It will be inevitable, however, that at this point we begin to organize and prioritize the content according to its relevance, thus taking the first steps in the making of the navigation tree of our product.
1.1.2.Sorting of cards
With card sorting (card sorting), we will get group the information in our application based on the user's mental model, since they are to be the users themselves who participate in the categorization and classification of the content. To do this, we will present a series of cards (one for each unit of content, screen or category, according to our needs) and we will ask them to order, group and They prioritize according to their criteria and instinct.
There are two variants for this technique:
1) Open- Users can group content and create the categories themselves, according to their convenience.
2) Closed- Users sort content accordingly with a closed list of categories.
The technique of card sorting It is especially Recommended in applications of medium and high complexity.

1.2.Structures of navigation

Navigation systems have to help users to answer three fundamental questions:
1) Where am I? The user must know at all times where is, so it is essential that all the application screens are correctly identified.
2) Where have I been? In the web environment it is common to change the color tone of the links visited or guide the user through "breadcrumbs" (breadcrumbs). On mobile, however, these resources are more complicated to implement; on mobile it is more common to answer the question where do i come from? through the Using navigation elements (back button) or transitions to show the relationship between screens.
Navigation on an Android device
Fuente: developer.android.com
Source: developer.android.com
3) Where can I go? All navigation elements (buttons, links, menus) must be clearly identifiable and offer no doubt about their destination. In applications with several levels of depth in the navigation, it is advisable to always keep a visible button that allows you to quickly return to the main screen (Home).
To design the navigation structure of our application, we can resort to the classic navigation tree or sitemap of a web page, establishing the flow chart between the different screens, represented by rectangles. At this point, it is worth noting that There is no single correct way to structure the information, but more or less suitable ways.
Our job here, once again, is to decide which will be the best structure according to the needs and objectives of our users. And make this be consistent and predictable, in such a way that users feel comfortable and do not waste time trying Discover how to use the application.
Below we will see some of the most common structures in applications for mobile devices.
1.2.1.Structure hierarchical
It is perhaps the structure most similar to that of a page web, where the information is organized in the form of a tree from a main screen or page. It is a recommended structure in case of large volumes of information, since it helps the user to quickly find what you are looking for and easily navigate navigation.
The different depth levels of the navigation tree should always follow this principle: generalist content at higher levels and more specific in the lower ones. In order not to overly complicate navigation, a common practice consists of do not exceed three levels of depth starting from the main page.
Hierarchical navigation structure
Fuente: gráfico adaptado de McVicar (2012)
Source: graph adapted from McVicar (2012)
1.2.2.Structure linear
Also called nested doll (in reference to the Russian dolls), the linear structure provides sequential access to information, ordered in hierarchical form, going from the most general to the most specific.
Linear navigation structure
Fuente: gráfico adaptado de McVicar (2012)
Source: graph adapted from McVicar (2012)
Example of linear navigation structure on an Apple watch
Fuente: apple.com
Source: apple.com
Navigation of this type is simple and very intuitive in first instance. Allows the user to orient themselves easily and know where they are at all times thanks to the fact that it can only move forward and backward. However, it can also become very heavy, since we force the user to constantly move forward or backward through screens. Again, It is advisable not to exceed three levels of depth from the screen main.
To improve navigation in this structure we can use to:
  • Home button- to allow the user to jump to the main page without need to undo all the path done.

  • Navigation menu: to allow the user to jump quickly between categories.

1.2.3.Structure of hub
Very common in games or multitasking applications, the structure of hub It is ideal for creating an index on the home page from which users can They will move to the different sections of the application. We should not confuse the structure of hub with a menu, since while in a menu the different options available form part of the same product, with a hub we facilitate access to tools well differentiated, unrelated to each other. For this reason There is no hierarchy either. between the different options, beyond their position on the grid.
Structure of hub
Fuente: gráfico adaptado de McVicar (2012)
Source: graph adapted from McVicar (2012)
Once the user is within one of the options, this solution allows you to develop other navigation structures (hierarchical or linear, for example). To change from one option to another, the user must always go through the hub.
1.2.4.Structure in eyelashes
The tabbed structure (tabs) is convenient for show content that is the same hierarchical level.
Tab navigation structure
Fuente: gráfico adaptado de McVicar (2012)
Source: graph adapted from McVicar (2012)
Some recommendations for using this structure:
  • We have to clearly show which tab is active, how many there are eyelashes available and what is the content behind each tab.

  • It is advisable that each tab has a title that allows identifying the content behind it. If it does not fit, we can truncate the text, even if it is not completely advisable (in these cases we can make, for example, the text circulate through the tab as if it were a marquee when it is selected).

  • If we have more tabs than the screen can show, we have to indicate clearly the user can move them laterally, using, for example, arrows.

  • The tabs work well on horizontal, since vertically they are not usually well interpreted by users.

  • We must follow the design guides of each operating system regarding the use and location of tabs. In this sense, it is common in Android and iOS to allow the navigation between tabs by sliding your finger laterally on the screen (in addition to pressing above the tab title), as long as this gesture does not interfere with the interaction with the content in the application.

1.2.5.Structure of network
Heir to web pages and hypertext, the network structure We usually find it in games or experimental products, in which there is neither order nor hierarchy between the different contents represented. The user can browse freely through the sections, but without an index that orders them, which can cause some disorientation and problems when trying to recover content.
Network structure
Fuente: elaboración propia
Source: own elaboration

1.3.Representation of the information

Effectively transmitting any information is a challenge that It begins at the same moment we begin to represent it. Knemeyer (2003) describes the guidelines to follow when we design information:
  • Information has no value by itself, it only has value if it is communicated with success. If it is not understood or cannot be accessed, it is useless.

  • We must remain faithful to the objectives set, the reasons why We want to transmit the information, and find the best way to achieve it.

  • We must always keep in mind who we are addressing, how the experience is going to be experienced. information and what will be its consumption context.

To ensure that the information reaches the user in a way effective, we will try to provide it with these properties:
  • Relevant. Not only from the point of view of what the user wants, but also what the user need.

  • Clara. The information must be easy to integrate and understandable. We must eliminate all barriers that make understanding difficult or impossible.

  • Memorable. In a world characterized by the excess of available information, Only that information that remains in our memory is causing a true impact. one Well-designed information, therefore, will stand out from the prevailing information “noise.”

1.3.1.Design of the content
In the same way that when representing a play we I would like the public to come out talking about the story and not about how beautiful the dresses were, the content is going to be the first key to the success of our product, ahead of the navigation, design or its functionalities. And like these, it is essential to design the content of our product with the same criteria of efficiency, effectiveness and satisfaction that define the usability of our project.
When talking about content design we can distinguish between:
1) purely aspects formal, such as, for example, layout, typography, use of colors, styles, line spacing, etc.
a) Size and spacing: one of the classic problems with reading on a mobile device is the size of the font, which often forces the user to do zoom to be able to read comfortably. For this reason, the handwriting on a mobile phone must be proportionally larger than the one we would use on a computer screen, in the same way that the line spacing has to be noticeably older.
b) Ease of reading and contrast: to avoid unnecessary efforts to the user, we will ensure that the text in our application can be read comfortably in different environmental situations.
iPhone version (iOS)
Para leer lo más cómodo posible, en la aplicación Pocket el usuario puede seleccionar entre diferentes opciones de visualización del texto (brillo de pantalla, fondo, tamaño y tipo de letra).
To read as comfortably as possible, in the Pocket application the user can Select between different text display options (screen brightness, background, size and font type).
2) Aspects related to the style of writing: that the content is clear and understandable, well written and unambiguous. The three The following characteristics serve to guide the realization of that idea:
a) Pyramidal structure: most importantly, the core of the message, it must go to the beginning. On mobile, the upper third of the screen is the most visible area for the user.
b) Be brief, precise and scannable: we must treat each paragraph as an informative unit (one paragraph = one idea), avoiding the use of empty expressions. To facilitate quick reading, it is advisable to use resources such as bold for keywords or lists to facilitate scanning of the text. It is worth remembering that at user does not like reading on the screen.
c) Be understandable and close: the language must adapt to the objectives of the project, but it must always be simple, easily understandable and familiar to the user. Messages should never blame the user or make them feel bad about themselves.

2.Design for interaction

With the rise of smart mobile phones and tablets we have entered a new era of interaction design. As we have studied in the previous module, For the last forty years we have used the same paradigms for the interaction between people and computers, practically the same metaphor as the desktop. These paradigms are still fully current, but they are being progressively replaced by others, based on new forms, more direct, to relate to technology.
As Dan Saffer says, we are facing an opportunity that presents itself only once a generation: it is now that we are just beginning to design new ways of interacting with our devices, our environment and even with each other.

2.1.Gesture gallery

Below we present the most common set of gestures that are used for interaction with mobile device interfaces.
2.1.1.Touch
The touch (tap) is the most natural what can be do on a screen, the most primary and, therefore, the most important, since with it carry out most of the actions on a touch device: opening applications, operating buttons, select items, etc. For those who have never interacted with a touch screen, the touch is the easiest gesture to learn, since it will remind you of the click made with a computer mouse.
Variants of this gesture are the double tap (double tap) and the triple tap (triple tap), although the latter is very unusual and must be justified very good to use, since it can be difficult to execute for some users.
2.1.2.long touch
In this gesture, the long touch (tap and hold), the user you have to touch an element on the screen and not lift your finger for a couple of seconds, a fact that triggers alternative actions or the display of menus on this element. In some In some cases, the long touch can be compared to the right mouse button click, although its uses They vary depending on the operating system or application in which it is used. For example, about a keyboard, this gesture allows access to accented characters, while on an icon application, allows us to drag it and change its location.
Screenshot of an iPhone keyboard
Al hacer un toque largo sobre el teclado, aparecen caracteres alternativos o acentuados.
When you long touch the keyboard, alternative characters or accentuated.
2.1.3.Swipe
After the touch, the swipe action (swipe) the finger on the screen is the other most natural gesture that we can do on a touch device and with which the most varied actions can be carried out. The most basic is to move the content of the screen vertically, as if we were doing it with the rotating wheel of a mouse, to continue reading a web page, for example. Horizontally, this gesture is common to scroll through images from a gallery or change pages on the home screen.
The variants of this gesture have to do with:
  • The speed with which it is done. In fact, it is the user himself who, once accustomed to the movement of sliding your finger on the screen, you will begin to do it more and more faster and shorter to minimize efforts. This quick movement of the finger on the screen in an address is called flick and can be used to turn pages of a book, photographs from a gallery, scroll quickly through a web page, etc.

  • The number of fingers that we slide at the same time on the screen. we can design actions for two, three and even four fingers sliding at the same time and in the same direction on the screen, although for phones – given the size of their screens – it is It is advisable not to exceed two. On the other hand, on tablets you should not abuse gestures with three or four fingers, since they are uncomfortable and hinder the view of a good part of the screen.

2.1.4.Drag
With the drag gesture (drag) you can either move a element within the screen (for example, moving an icon to a new location or rearranging the elements of a list) how to move the focus of the screen itself when we have an image expanded to the maximum.
To some extent, this gesture can be confused with doing swipe (swipe) on the screen: when we drag, however, normally we are interacting with a specific element (an icon, an enlarged image), while the Swipe gesture is normally done to navigate or scroll.
Depending on where the drag gesture is started, it is also used to display notifications (by dragging vertically, from top to bottom and starting outside of the screen) or the menu within an application (dragging horizontally, starting from outside the the screen).
2.1.5.Separate and pinch with two fingers
The gesture of separating with two fingers (spread) is over becoming synonymous with expanding (zoom in) what we have on the screen, and as such it is a behavior expected by users, especially when viewing photographs, consulting a map service or use the web browser. Its opposite, that is, making the gesture of pinching the screen (pinch), does the reverse action, moving away (zoom out) that which we have on screen.
There are applications that are using the separate and pinching for other purposes, beyond enlarging or reducing what we have on the screen. By For example, in Google Photos we can use the pinch and spread gestures with our fingers on the screen to reduce or enlarge the size of the photos on the timeline from the application, open and close photos...
2.1.6.Rotate
With this gesture we rotate (rotate) on its axis content displayed on the screen. It is a common gesture when viewing maps and, combined with that of separating and pinching, allows you to control the interface with agility and precision.
2.1.7.Twist and rotate the device
The accelerometer and gyroscope that most Mobile devices are capable of detecting changes in their orientation, from vertical (Portrait) to horizontal (Landscape) or vice versa.
Although it is not a gesture that is made directly on the screen, This change in screen orientation has quickly become a normal behavior. expected by users, especially when viewing photographs or videos.
Rotate and rotate the device
Fuente: elaboración propia
Source: own elaboration
This gesture, however, can be used for more things than just allow a more comfortable view of the screen:
1) Alternative views of the interface can be designed depending on the orientation of the device. This resource can go beyond simple reordering of the elements shown on the screen, offering new functions to the user. a good For example, we have it in the calculator, which offers the basic controls vertically, while in horizontal – having more space to place buttons – offers the controls of a calculator scientific:
Example of an alternative view depending on the Device orientation in iPhone calculator app
Ejemplo de vista alternativa en función de la orientación del dispositivo en la aplicación de calculadora para iPhone
Another example is the iPhone calendar, which with the device Vertically it shows a single day, while horizontally it shows five:
Alternative views in the calendar of an iPhone in depending on device orientation
Vistas alternativas en el calendario de un iPhone en función de la orientación del dispositivo
The availability of these must be made very clear to the user. alternative views, since otherwise they might go completely unnoticed. Although it is true There may be users who enjoy discovering these options on their own, most You will always appreciate receiving clear information about what you can and cannot do with your device.
Message on a Samsung Galaxy Tab
Algunos dispositivos Samsung (Android) permiten controlar el zoom en pantalla inclinando el dispositivo.
Some Samsung devices (Android) allow you to control the zoom on the screen tilting the device.
2) The accelerometer and gyroscope can also be used to convert the device itself into a controller, a common resource in games that allows users users, for example, control the direction of a vehicle on a road simply by turning the device.
Control settings in motorcycling game SBK16 for iPhone (iOS)
Configuración de controles en el juego de motociclismo SBK16 para iPhone (iOS)
3) In augmented reality (AR) applications; augmented reality), this gesture becomes the main way to interact with the interface, since which is by rotating the device how it shows you, as if it were a window, the layer of information about the images provided by the camera.
Example of augmented reality
El juego Pokémon Go para móviles permite buscar y capturar estas criaturas sobre escenarios reales, mediante realidad aumentada. Fuente: https://mediad.publicbroadcasting.net/p/shared/npr/styles/x_large/nprshared/201606/483862852.jpg).
The game Pokémon Go for mobile allows you to search and capture these creatures on real scenarios, through augmented reality. Source: https://mediad.publicbroadcasting.net/p/shared/npr/styles/x_large/nprshared/201606/483862852.jpg).
2.1.8.Move
The accelerometer also allows us to detect when the user moves laterally and repeatedly (shake) your device, a resource we can tap to activate a specific action, create shortcuts to common functions (for example, play or stop the music player, dismiss a call) or facilitate interaction or exchange of information with other devices.
Move
Fuente: elaboración propia
Source: own elaboration
For example, in the iOS operating system, the swipe gesture In this mode the device allows undo (undo) the last action, while in applications such as Line (instant messaging), allow you to add new contacts without the need to have to enter them manually.
2.1.9.squeeze
This gesture has become popular since the appearance in the market for the Apple Watch and the iPhone 6S and iPhone 6S Plus models. Its screens allow you to detect the intensity with which the user presses the screen, thus recognizing up to three types of interactions: classic touch and gestures peek and pop.
squeeze
Fuente: elaboración propia
Source: own elaboration
We could translate peek like "snooping", or whatever same: take a quick look. This is the shallowest pressure, with which we can, for For example, preview a photo from the camera roll or click on a link to preview the page that is in it without leaving the screen we are on. Once this view is displayed quickly, by sliding the finger up we access the available options, lifting the finger We close the screen and pressing even harder (do pop) we definitely open the selected item.
Thus, as if it were a bubble, the gesture of pop It is equivalent to “exploding” the preview and bringing the content to the foreground. It is, for therefore, from the firmest pressure on the screen.
Examples of peek and pop on an iPhone 6S
Con los gestos de peek y pop en un iPhone 6S podemos seleccionar una opción concreta antes de abrir una aplicación (izquierda) o hacer una vista previa de un enlace mientras navegamos por internet (derecha).
With the gestures of peek and pop on an iPhone 6S we can select a specific option before opening an application (left) or making a view preview of a link while browsing the Internet (right).
Due to the multiple possibilities offered by this new form of interaction, it can be expected to spread rapidly to other devices and operating systems, and that application developers find new uses for it. On the other hand, pressing a screen with different levels of force requires some training and expertise on the part of users, which can make it difficult for mass adoption and for it to become a normal behavior. expected as has happened with other gestures.

2.2.Graphic elements

Below we will describe some of the graphic elements that we can usually find in the interfaces of mobile devices.
2.2.1.Typography
The text is the basic element with which we will build the content of our applications. We will use it everywhere: in the body of our messages, in menus and navigation bars, in buttons... Make a good choice of typography and Taking care of issues such as line spacing or spacing will result in better readability of our application and, therefore, greater convenience for our users.
Operating systems usually have standard typography (Roboto for Android, San Francisco for iOS and Segoe for Windows Phone), although it is not mandatory to use it in our products. In case you want differentiate ourselves from the guides set by the operating systems, some guidelines and advice:
  • Better sans serif. Dry stick typefaces, without serif, are more clean and comfortable to read on the screen, especially when it is small. If the design allows it, we can play with two different fonts (for example, one for the titles and another for the body of text).

  • Font size. It must be large enough to be read. comfortably (we must avoid at all costs that the user feels the need to zoom in with the fingers to enlarge the letter), although without going overboard: a text that is too large will cause many line breaks, making reading difficult. A simple way to calculate it is by counting the number of characters that fit on one line: thirty to forty characters per line is a good starting point.

  • Color and contrast. Although it may seem to go against common sense, it is not It is always necessary to resort to "black on white" to achieve legible text. In fact, in In some cases, pure black on white may even make reading difficult or fatigue the user. user. To soften the contrast, shades of gray can be used (both for the background and for the the letter). For example, instead of “pure” black text (#000000), we can use dark shades of gray, such as #0D0D0D or #0F0F0F for the font, or very light tones.

  • Hierarchies. While on the web we have become accustomed to the use of multiple levels (H1, H2, H3, H4, etc.), on small screens two will often be enough levels to hierarchically organize our text; To make the topic easier, we can play with variations (bold, italic) to have greater typographic richness.

  • Spacing. As in the previous point, on small screens We will slightly increase the spacing – both between words and between lines – to improve the text readability. We can also apply this increase in space between paragraphs, helping This helps the reader better identify blocks of text. Again, it is not advisable to go through excess: text with too much white space between words or lines is uncomfortable to read.

  • Responsive Typography. If our application is going to be used in different screen sizes, it is advisable to make sure that both the font size and the spacing are scaled appropriately.

  • Alignment. The basic rule is to avoid justified text, since in On certain occasions it can leave us lines with too many blank spaces. For the rest of alignments, the general recommendations are:

    • Left alignment. This is the preferred alignment, since It works great on all occasions, even with large blocks of text.

    • Centered text. It is advisable to use it in moderation. It works either with titles, within buttons or in small blocks of text.

    • Right alignment. It should also be used in moderation and small blocks of text.

2.2.2.Icons
Icons are usually used as shortcuts to access to applications from the home screen such as to access specific items or functions once inside these. It is advisable that the icons are accompanied by text for easy identification. This label is usually located below the icon and centered on the image. The label should not occupy more than one line; If it is too long, it can be truncated the text or pass it off as if it were a marquee.
We can find several types of icon:
1) Fixed icons: represent the element with an image or function to which they give access. The image has to be very clear and understood at first glance.
iOS operating system icon set
Fuente: developer.apple.com
Source: developer.apple.com
2) Interactive icons: not used to access applications, but to carry out direct actions, such as, for example, connecting the WiFi or the GPS, adjust screen brightness, etc. Its design must allow you to quickly view the element status.
Interactive icons in the control center of a iPhone (iOS)
Iconos interactivos en el centro de control de un iPhone (iOS)
2.2.3.Widgets
If we had to define them in some way, the widgets They are like "small windows" that allow us to consult the content of a application without having to open it.
On Android, the widgets play an essential role in the customization of the user's home screen. For developers, widgets represent an opportunity for both promotion of the application as loyalty of the user: a widget on the user's home screen is a fantastic "hook" to capture your attention and encourage you to open our application.
We can classify the widgets according to the following categories:
1) Widgets of information: used to show variable content or content that the user wants to quickly follow up on on their screen start. Typical examples of widgets of information are meteorology or the clock. At touch on it widget, the associated application opens with an expanded view of the information.
Widget of meteorology on Android
Fuente: developer.android.com
Source: developer.android.com
2) Widgets collection: as its name suggests, this widget shows multiple elements of the same class (for example: emails electronics, photographs...). This type of widgets They usually allow Vertical scrolling to navigate content. By tapping on it widget, opens the associated application with an expanded view of the selected information or content.
Widget collection
Fuente: developer.android.com
Source: developer.android.com
3) Widgets control: its use is similar to that of a switch, allowing the user to activate or deactivate certain functions or parameters of configuration without having to leave the home screen. A typical example is found in the Android quick settings or in the widget that allows you to control the playback of audio on the device.
Widget quick settings
Fuente: developer.android.com
Source: developer.android.com
4) Widgets hybrids: are those that combine two or more of the previous categories. For example, a widget to control the music playback can at the same time be a widget control (with buttons for start or stop playback, skip tracks...) and an information one (showing the name of the artist, song name, album title...).
Widget music playback on android
Fuente: developer.android.com
Source: developer.android.com
2.2.4.Notifications
Notifications serve to warn the user of alerts or changes in status of the system and applications. The clearest example is the notice of a missed call or the arrival of a new chat message, but notifications are also can be used to show the user the next event marked in their agenda or alert them about new updates available for the system.
Normally, it is the operating system itself that determines how and where notifications are displayed, with the following general characteristics:
1) At a minimum, the notification includes the icon the application that has generated it, a title and text with the content of the notification and one timestamp from the moment it was generated. It is common for notifications come accompanied by a sound to attract the user's attention.
«Anatomy» of a notification on Android
Fuente: developer.android.com
Source: developer.android.com
2) Some operating systems allow view "expanded" of the notification, which in certain cases even allows taking actions directly on the notification, avoiding having to open the application (for example, reply to a message or delay an alarm).
Expanded notification on Android Wear
Fuente: developer.android.com
Source: developer.android.com
3) When faced with a new notification, the user has to be able to decide if you want to attend to it or leave it for later. The most common thing is to show the notifications just for a few seconds through a strip, animated or not, that appears for a few seconds at the top of the screen.
4) If you show the notification through a popup window (pop-up), the user must be offered the options of responding to the message or leave it for later.

3.Principles for design of mobile interfaces

Below we present the basic principles for the design of mobile interfaces.

3.1.Simplicity

Walking down the street, down some stairs, in the waiting room from the dentist, on the bus on the way to work... users use their mobile devices in the varied situations, subjected to constant interruptions and very often without giving them 100 % of your attention. It is for this reason that mobile interfaces have to be easy to use from the first moment: in general, the user will perceive as a setback having to stand in the middle of the street to find out how the app you just downloaded works.
We will achieve simplicity in our designs when any person can understand and use the interface regardless of previous experience, training or concentration level. To do this, we will have to present the user first only those essential options to achieve your objective or complete the central task of the application. An interface full of buttons and options will baffle the user. On the other hand, if We give you few options, the user will quickly learn the gestures necessary to manipulate with success the interface, making it increasingly pleasant to use. The rest of the options They can be hidden behind a menu or appear progressively, as the user go using the application.
Other basic guidelines for simplicity are to identify and title clearly the controls and navigation elements, offer a clear answer for all the actions or ensure that the messages and texts in our interface are unambiguous and they understand well at the first.

3.2.Efficiency

The efficiency of an interface is defined by the number of steps what the user has to give to achieve a certain objective. The most important tasks, for Therefore, they have to be clearly accessible and completed with the fewest number of touches or movements on the screen.
In this sense, we can take advantage of the device's sensors to save the user from having to enter data manually (for example, by offering automatically the weather forecast for the city where you are) or remember your preferences from one session to the next, learn from your use of the application or even predict your next action, all with the goal of making your job easier.

3.3.Consistency

According to the consistency principle, users will learn to handle an interface more easily when they can transfer previous knowledge into new contexts. In this way, the interface of our application has to be consistent with itself itself, with the device and with the operating system where it will be installed, and if possible, with the rest of the applications with which it will coexist.
This does not mean that our application has to be like all the others. the others, but, even if it is innovative, the user will have to find the application easy to use because it respects the standards and paradigms of the operating system of the device.
There are four types of consistency:
  • Aesthetic consistency: refers to the visual appearance (logos, colors, fonts, graphic resources), which allows rapid recognition of the system by the user.

  • Functional consistency: is what allows the user to apply knowledge previous ones in a new context. For example, the controls in a video application replicate the "old" symbols used on VHS video players (play, pause, rewind, forward...), which which makes it easier for the user to control from the first moment.

  • External consistency: in the case of mobile applications, refers to the consistency of the application with the design principles of the operating system or respect for the established design patterns.

  • Internal consistency: refers to the coherence of the design of the application, its visual and functional unity, which provides peace of mind and confidence to the user while driving it. For example, the buttons are always in the same place and have the Same behavior on all screens.

3.4.Interaction

In humans, the sense of touch is a tool essential to interact with our environment, perhaps the most intuitive. Until very recently, This way of interacting was not possible in virtual environments. With the rise of screens on mobile devices, haptic interaction (from the Greek haptikos, 'relative to the sense of touch') has become popular, since it allows users to directly manipulate the objects on the screen. This fact increases your feeling of control over the interface and It allows them a quick and better understanding of the consequences of their actions.
Screenshots of the Microsoft Outlook application for iPhone
La aplicación para gestionar el correo electrónico Microsoft Outlook permite configurar gestos sobre las filas en la bandeja de entrada para marcar como leído, borrar, archivar o posponer fácilmente el correo recibido.
The Microsoft Outlook email management application allows configure gestures on rows in the inbox to mark as read, delete, Easily archive or snooze received mail.
To reinforce this sensation, the device must respond faithfully to the user's movements. In this sense, the user can also receive one haptic response to your actions, usually through device vibration when you use the virtual keyboard or press a button on the screen. On devices like the iPhone 6S or the Apple Watch, this type of response has been enhanced with the introduction of technology Force Touch, which allows recognition of the pressure of the user's finger on the screen.
Finally, interaction with mobile devices can occur both by touching the screen and by moving the device itself (for example, rotating the screen), thanks to the motion sensors they incorporate.
When designing the interface, it is advisable to always keep in mind It counts all the ways the user will try to interact with it, not just those that we have thought and designed.

3.5.Metaphors

If we present the objects and actions in the interface as a metaphor for objects and actions in the real world, users will quickly learn to interact with the interface and will find it more attractive.
The classic example in this sense is the folder: people use folders in the real world to store documents; in the interface, therefore, a folder will be quickly identified as a containing element. Other common metaphors in interfaces are the toolbox or gears to represent configuration options, a letter envelope for email, a headset for the telephone, etc.
These metaphors need not be limited to icon design. or other graphic elements: for example, they can also be used to design the gestures that later the user will have to do, such as turning the pages of a book with his finger, turning on or turn off switches or change the date on a spinning wheel.

3.6.Answer

The feeling of control derived from direct manipulation of the interface on the part of users must be reinforced at all times by a response quick, immediate, to their actions. This response confirms the action taken to the user, who then Otherwise you might feel frustrated or try the same action repeatedly, producing distortions in data entry.
Buying plane tickets by phone mobile
Let's imagine, for example, someone who wants to buy tickets. plane via your mobile phone. Using a form similar to the one you would find in a web page, enter origin, destination, number of passengers and the desired round trip dates. Then press the button that activates the search, but nothing seems to happen. Wait a few how many seconds, and press it again, this time paying attention to whether the button responds in any way. way at the touch of your finger, which does not happen. Then you begin to doubt whether the application works, press the search button a few more times and then try to log in again, also without success, in the form fields. It seems that the application has been left effectively "hanging." But just at that moment, the screen changes showing him the results of your search.
In this example, we can distinguish two types of response to the user action that have failed. First of all, the user has not noticed any reaction when you pressed the search button, which made you distrustful. Secondly, when He pressed the button again, he saw that it did not react to his gesture, and this made him distrust even more.
The speed of response to a user action does not It means that the system has to be equally fast processing your request. Said from another mode: the user may not instantly obtain what he or she requests from the system, but he does have You have to know at the moment that the system is working on it.
In the example we just saw, repeatedly pressing The search button has no negative consequences for the user, but if this were to happen elsewhere in the application, for example, when paying for tickets, it could well be that the user will end up paying their tickets twice or more.
On the other hand, the feeling of response goes beyond using response indicators. On touch screens, the responsive feel can be achieved through changes in the position, orientation, color and lighting of the actuated element, animating it subtly with sounds or even briefly activating the device's vibration mechanism. A good part of these responses are predetermined by the operating system itself, so that With their continued use, they become expected behaviors on the part of users.
In this sense, it must be taken into account that the user will value the speed of your device's response over aesthetics, so before design complex animations, we will have to be very clear that the device will be capable of carry them out fluently.
Buttons on Android
Los botones en Android tienen diferentes estados, cambiando de aspecto y color cuando el usuario los toca. Fuente: developer.android.com
Buttons on Android have different states, changing appearance and color when the user touches them. Source: developer.android.com

4.Sketching and wireframes

However, there is no ideal time to start prototyping. our ideas. In fact, there is so much debate about when start prototyping as about how prototype If we consider it linearly, the process would be something similar to this:
1) Sketching: we begin to give shape to our ideas making quick sketches on paper. It is the most initial stage, of brainstorming, where ideas They must flow freely.
2) Wireframes: ideas begin to take shape and We begin to organize in boxes, lists, menus, etc. At this stage is when we begin to prioritize the information, designing the navigation tree of our application.
3) Mockups: we add detail to our wireframes: color, fonts, photos and other visual elements to give the design greater realism. Eventually, we add interaction to the designed screens, either linking them together to simulate real navigation or adding other animations/interactions to achieve a advanced prototype.
4) Development: in a very summary way, we will say that in this phase It is about writing the source code in the chosen programming language to convert the prototype into a real product.
The first two phases correspond to low fidelity prototyping, while in the third (mockups) we would already be talking about high fidelity prototyping. However, in all of them we must work following the principles of user-centered design. user, iterating our designs according to the scheme we saw in the previous module:
Fuente: elaboración propia
Source: own elaboration
So, when we refer to “loyalty,” we are talking about visual detail and interaction in our prototypes. Hence, low fidelity prototypes are common (and recommended) in the early stages of our project, where we convert our ideas into something tangible. High fidelity prototypes, for their part, are common in iterations more advanced, when the ideas are clearer and we want to refine our designs.
Even so, there are other factors that affect the level of loyalty with that we will work on our prototypes. For example:
  • Available budget for the project, both in money and time. Yes We don't have much of one or the other, our prototypes will be fast and in low fidelity, which just to draw the main lines of the project.

  • Resources and ability of the design and development team: the prototypes in High fidelity requires specialized personnel who master prototyping tools.

4.1.Low prototyping fidelity

As we have seen, low fidelity prototypes (sketches and wireframes) are usually done in the early stages of development, just when we begin to Think about what the functions of the application will be. You can start doing them with pencil and paper, without worrying much about the design. In this phase the most important thing is to visualize what we really want to achieve and how we want to do it.
Pencil and paper prototype
Fuente: Flickr
To help us visualize what we do even better, we can make these first drawings within the framework of a mobile device to get an idea of the sizes and proportions of the elements that we place on the screen. On the internet you can find multitude of printable templates – real size – for both phones and tablets, which They will make our work easier.
Starting to work in low fidelity offers us three advantages basic:
  • Speed: Design iterations and improvements happen quickly. Simply tear out the page and start again.

  • Efficiency: By not focusing on visual details, our designs go straight to the point, thus making it easier for us to direct all our attention to the key points of our product.

  • Collaboration: Anyone knows how to draw with paper and pencil. Share the First sketches with all the participants in the project will allow us to easily collect ideas and improvements by all team members.

We can also design the navigation tree of the low fidelity application, where we will propose all the possible paths of screens that you can traverse the user.
The navigation tree can be inspired by the diagrams of flow of a computer program or in the sitemap from a website, in which They indicate all the screens and the paths that the user can take between them.
Some recommended tools to work with wireframes they are:
1) Balsamiq: perhaps the most classic, which began as a web page prototyping tool and is now used also for mobile applications. Allows you to create and share prototypes easily and quickly, simply by dragging and dropping items from the top tools menu. The The final result looks as if it were done by hand, which allows us to focus more on the navigation structure than in the design.
Balsamiq tool palette
Fuente: balsamiq.com
Source: balsamiq.com
It can be installed on the computer – the cost of the license for a user is 89 dollars – or use it directly on your website, with a basic subscription cost of 12 dollars per month (taken from https://balsamiq.com/buy/#d; consultation date: November 21, 2012).
2) NinjaMock: online tool that allows you to easily create prototypes and share them online for testing or evaluation. The prototype pages can be linked together, making it easier to navigate. Includes tool palette and stencils for Android, iOS and Windows Phone. NinjaMock is free and fully functional, although the projects in the free version are public and carry the company brand.
NinjaMock
NinjaMock
3) Pop: This original application allows us to photograph our wireframes made to paper and pencil and add interactions through links, so that our drawings come to life. The resulting prototypes can be shared with other users for input. feedback. Available for free for iOS and Android.
Android version of POP
Fuente: play.google.com
Source: play.google.com
4) Draw.io: free online tool (works even without user registration) that allows you to quickly and easily create flowcharts, trees navigation and even low-fidelity prototypes of our applications. Allows you to save the projects on cloud hosting services, such as Google Drive, Dropbox or OneDrive, as well as export the diagrams in different formats (.gif, .png, .jpg, .pdf...).
Flowchart in draw.io
Diagrama de flujo en draw.io