More than ever, designers are being asked to create experiences for a variety of mobile devices. As tablet adoption increases and we move into the post-PC world, companies will compete for users’ attention with the quality of their experience. Part of designing successful apps for Android tablets requires not only a great concept that will encourage downloads, usage and retention, but also an experience that Android users will find intuitive and native to the Android environment.

The following will help designers become familiar with Android tablet app design by understanding the differences between the iPad iOS user interface and Android 3.x “Honeycomb” UI conventions and elements. We will also take a look at Honeycomb design patterns and layout strategies, and review some of the best Android tablet apps already out there.

Note: While Android 2.x apps for smartphones can run on tablets, Android 3.0 Honeycomb was designed and launched specifically for tablets. Future updates promise to bring Honeycomb features to smartphone devices in addition to making it easier to design and build for multiple screen types.

For most of us, our first exposure to tablets was via the iPad. For this reason, it’s reasonable to begin comparing the two user interfaces. By comparing, we can align what we’ve already learned about tablets and begin to focus on what important differences there are to meet the unique UI needs of Android users. This not only helps us get up to speed, but becomes especially important when designing an Android tablet app from an existing iPad one.

It’s just like the iPad, right?

While the Android tablet and iPad experience share many similarities (touch gestures, app launch icons, modals, etc) there are also many differences that designers need to be aware of before making assumptions and drawing-up screens.

Screen Size and Orientation

The biggest difference between the two platforms is the form factor. Layouts for the iPad are measured at 768 x 1024 physical pixels and the iPad uses portrait mode as its default viewing orientation.

With Android tablets it gets a bit more complicated due to multiple device makers. In general, there are 7” and 10” Android tablets screen sizes (measured diagonally from top left corner to bottom right corner) and sizes in between. However, most tablets are sized at around 10”.

What does this mean in pixels? A good baseline for your layouts is 1280 x 752 (excluding the System Bar) based on a 10” screen size using landscape—not portrait—as the default orientation. Like the iPad, content on Android tablets may be viewed in both landscape or portrait view, but landscape mode is how it’s generally used.

Viewing a web page on both Android Tablet and iPad in portrait mode

Viewing a web page on both Android Tablet and iPad in landscape mode

However, for Android screen size is only half of it. Android tablets also come in different ‘screen densities‘ — that is the number of pixels within a physical area of the screen. Without going into too much detail, designers must prepare all production-ready bitmaps for three different screen densities by scaling each bitmap 1.5x and 2x its original size so that a bitmap originally set at 100 x 100 pixels also has copies at 150 x 150 and 200 x 200. By making three batches of graphics scaled at these different sizes, you will be able to provide any necessary bitmaps for medium, high and extra high density tablet screens without losing image quality.

Note: For more information on screen densities and graphics preparation for Android devices, refer to my previous article on Designing for Android.

System Bar

While iOS makes minimal use of the System Bar, Android Honeycomb expands its size to include notifications and soft navigation buttons. There is a Back button, Home button and a Recent Apps button.

The Android Honeycomb System Bar and buttons are always present and appear at the bottom of the screen regardless of which app is open. Think of it as a permanent UI fixture. The only exception is a ‘Lights Out Mode’ which dims the system bar for showing immersive content such as when playing a video or game.

Back Button

While the bulkiness and permanence of the Honeycomb System Bar might appear as an obstacle to designers, it has the advantage of freeing-up real estate typically taken by a ‘Back’ button in apps for the iPad. The Honeycomb System Bar has a ‘Back’ button that works globally across all apps.

Action Bar

The bulk of the UI differences between platforms is concentrated in the top action bar. Android suggests a specific arrangement of elements and visual format for the tablet Action Bar that includes placement of an icon/logo, navigation (e.g. drop-down menu or tabs), and common actions. This is one of the most unifying design patterns between different Android Honeycomb apps and worth taking the time to familiarize yourself with before attempting customization or something iPad-like. More on the pervasive Action Bar later.

Widgets

New to iPad users will be Android’s widgets. As the name describes, they are small notification and shortcuts systems users can set to appear on their launch screen. Widgets can be designed to show stack views, grid views, list views and with Android 3.1, are now re-sizable.

Notifications

While iOS’s notifications push simple alerts to your launch screen, Honeycomb offers rich notifications that pop up (“toast” we used to call it) at the bottom right area of the screen much like Growl on Mac OS X. Custom layouts for notifications may include anything from icons to ticker text and actionable buttons.

Settings

Most often, any settings within an iPad app are presented from a popover triggered by an ‘i’ button. Settings categories are broken up into tables for easy visual separation. Honeycomb has a different convention that looks more like the iOS General Settings screen with the ability to navigate categories on the left and view detail on the right. This is the preferred (and more elegant) way of presenting multiple settings in Honeycomb.

UI Elements

As you can imagine, Android goes to great lengths to do everything opposite its competitor (that’s called differentiation!). Honeycomb has its own UI conventions and new ‘Holographic UI’ visual language for such mundane actions as picking a time/date, selecting an option, setting volume, etc. It’s important you understand this UI language for building screen flows and creating layouts.

Fonts

Question: How many fonts does iPad 4.3 allow you to use?

Answer: 57

Question: How many does Android?

Answer: 3

Yep, that’s Droid Sans, Droid Serif and Droid Sans Mono. However, there is an upside: While that’s all you get with the platform, designers and developers are free to bundle any extra fonts with their app.

Anything the same?

Luckily for designers already familiar with the iPad, there are some similarities between the two platforms:

Touch Gestures

Tap, double tap, flick, drag, pinch, rotate and scroll at will.

Split View and Multi-pane UI

Split View is one of the most commonly used layouts for tablets consisting of two side-by-side panes. Of course, you can design additional panes for more complexity.

Embedded Multi-Media

Both platforms allow embedded audio, video and maps.

Clipboard

For copying and pasting data in and out of separate applications.

Drag-and-Drop

Both platforms have drag-and-drop capabilities.

Design Patterns

Honeycomb carries over many of the same design patterns introduced in Android 2.0 and expands on them. In case you’re not familiar with design patterns, Android defines them as a “general solution to a recurring problem.” Design patterns are important UI conventions designed by Android to help unify the user experience and provide designers and developers a template to work from. They are also customizable, so no need to fret!

As mentioned before, the Action Bar is the most prominent Android UI component and the one we’ll focus on.

Icon/Logo

The Action Bar begins with an icon or logo on the far left and is actionable. By tapping on it the user will be directed to the app’s home screen.

Navigation

Next, we typically find some mode of navigation in the form of a drop-down or tab menu. Honeycomb uses a triangle visual to indicate a drop-down and a series of underlines for tabs which typically take up the majority of the Action Bar real estate.

A left arrow button may also appear to the left of the icon/logo or label for navigating back or canceling a primary action.

Common Actions

Common Actions are as their name implies providing the user with such things as search, share and an overflow menu. They are always placed on the right side of the Action Bar away from any tabs.

Overflow Menu

The Overflow Menu is part of the Common Actions group and is sometimes separated by a vertical rule. The purpose of the Overflow Menu is to provide a place for miscellaneous menu items such settings, help, feedback, etc.

Search

Search is also a part of the Common Actions set. Unique to Search is its expand/collapse action. Tap on the Search icon and a search box expands out for entering your query. Tap the ‘x’ button to cancel and it collapses to its single button state. This is a space saver when you already have many actions or tabs you need to show.

Contextual Actions

Contextual Actions change the format of the Action Bar when an item is selected to reveal actions unique to that selection. For example, a photo app’s screen of image thumbnails might have an Action Bar that changes once an image is selected. In this case, the Action Bar might change to show contextual actions for editing that particular image.

To exit the Contextual Action Bar, users can tap either ‘Cancel’ or ‘Done’ appearing in the far right area of the bar.

Tablet Layout Strategies

Using Fragments and Multi-Pane Views

The building blocks of Honeycomb design are Fragments. A Fragment is a self-containing layout component that can change size or layout position depending on the screen orientation or size. This further addresses the problem of designing for multiple form factors by providing designers and developers a way to make their screen layout components elastic and stackable depending on what screen restraints the app is working with. Screen components can be stretched, stacked, expanded or collapsed and shown or hidden.

What makes Fragments so special? With a compatibility library, developers can bring this functionality to Android smartphones back to Android 1.6, giving designers and developers the option of building an app using a one-size-fits-all strategy. In short, this will allow designers and developers to build one app for everything.

While Fragments may be a term used more by developers than designers, it’s good for designers to adopt the perspective that capsules of content can be stretched, stacked, expanded and hidden at will.

The most common arrangement of Fragments is the split view. This layout is common for news apps and email clients where a list is presented in a narrow column and a detailed view in a larger one.

Another way of presenting a split view is to turn it on its side. In this case, the sideways list Fragment becomes a carousel, navigating horizontally instead of vertically.

Orientation Strategies

While use of Fragments is great for applying one design to multiple screen sizes, they are also useful for setting orientation strategies. Your screen design might look great in landscape but what are you going to do with three columns in a narrow portrait view? Again, we have the option to stretch, stack or hide content. Think of Fragments like a bunch of stretchy puzzle pieces that you can move around, shape or eliminate as needed.

A Word About Animation

The Honeycomb framework allows designers and developers to use a variety of animation effects such as “fades or movement between states, loop and animated image or an existing animation, change colors, and much more.” Honeycomb also boasts high-performance mechanisms for presenting 2-D and 3-D graphics. For a good overview of what Honeycomb is capable of, check out this video.

Learning from Example

Designing apps for Android tablets is still relatively a new space with some brands beginning to test the waters. Below is a list of apps for inspiration. You can download any of the apps from Android Market or Amazon.com.

YouTube

Naturally, Google’s YouTube for Honeycomb is an exemplar app showcasing all the design patterns and UI elements discussed above. To get a real feel for Honeycomb, download this app first and take it for a spin.

CNN

The CNN app makes good use of touch gestures (flicking to view additional content), split view and fonts! In this case, they’re using a custom font (Rockwell) for news headlines.

CNBC

Another good news app with examples of animation (stock ticker tape) and rich graphics and gradients. CNBC has one of the most visually compelling apps.

Plume

With it’s three column layout, Plum is a good example showing how layouts may need to change dramatically from landscape to portrait views.

FlightTrack

A data-heavy app done elegantly. Includes nice examples of maps, subtle use of animation, and standard Honeycomb UI elements.

Pulse

What else can you say…it’s Pulse for Android tablets! It’s still fun to compare the Android tablet version with the iPad one which is identical in almost every way.

WeatherBug

This was one of the first Honeycomb apps in Android Market and makes good use of maps and the Holographic UI for showing pictures from weather cams.

Kindle

Kindle pretty much sticks to the books when it comes to using design patterns and Honeycomb UI elements. Nevertheless, the outcome is very elegant while staying true to Android’s best practices.

Honorable Mention

IMDb
News360
USAToday
AccuWeather
Ustream
Google Earth
Think Space
Gmail

Online Resources

Videos

Designing and Implementing Android UIs for Phones and Tablets (Google I/O 2011)

Android 3.0 Honeycomb Animation Demo

Presentations

Designing and Implementing Android UIs for Phones and Tablets (Google I/O 2011)

Blogs

Tablet UI Patterns

Android Developers

Supporting Multiple Screens
Icon Design
Android 3.0 Platform Highlights

The problem with re-skins is that they are usually a means of covering up more serious problems with the product or service. Sometimes it’s even a last resort: “We don’t know what to do. Why don’t we re-skin it and make it look better?”. Many executives may see a re-skin as a quick way to improve a poorly perceived user experience. It’s not always in the client’s best interest for a designer to accept a project they know is only a band-aid covering more serious design issues. At the very least, a professional should be up-front with the client and let her know what real issues may lie under the hood.

I don’t want to demean the importance of having a good visual design for a product or service. According to the book, Universal Principles of Design, aesthetic designs:

“…look easier to use and have a higher probability of being used, whether or not they actually are easier to use. More usable but less-aesthetic designs may suffer a lack of acceptance that renders issues of usability moot. These perceptions bias subsequent interactions and are resistant to change. For example, in a study of how people use computers, researchers found that early impressions influenced long-term attitudes about their quality and use. A similar phenomenon is well documented with regard to human attractiveness—first impressions of people influence attitude formation and measurably affect how people are perceived and treated.”

But visual design is much more than just a nice paint job. Not only does good visual design help create the illusion of ease-of-use, it also helps promote a positive emotional response and connection to the brand. Marketers know this well and will take every opportunity to try and produce a good feeling in the hearts and minds of their customers. We are sentient (from Latin – sentient: feeling) beings that for good or for bad, make decisions based on our emotions. However, good visual design is only part of what makes a great user experience much like a car’s exterior is only part of what makes a car delightful to own. Not only is functionality important (whether or not it actually works), but so are factors of usability and perceived value. Without a usable interface or a product or service that means something to the user, there’s no point in good visual design—it’s nothing more than cosmetics.

So, the first question a designer should ask a client requesting a re-skin is “Why?” (this is no time to be shy). Another should be, “What do you expect to gain from a re-skin?” The idea isn’t to ridicule the client, just to dig deeper and possibly bring to light more severe problems such as poor navigation, page flow, features, nomenclature, copy, etc. Sometimes the stakeholders have little experience with product design and simply don’t know what makes a good user experience. This particularly occurs with business-focused and technology-focused teams where there is no user advocate.

So, when does a re-skin make the most sense? Obviously, a re-skin is a good idea if a company is changing its brand identity. But even then, a re-skin isn’t just about making it look good and making it easy to use with big buttons and spacious layouts. A designer must ask “For what kind of user am I designing this for?” “What kind of emotional response am aiming for?” Even the visual design of an application like a word processor or email client will elicit some kind of emotion from the user.

Another good time to consider a re-skin is when there are big changes to content and functionality. Why not launch this year’s model with a slightly new look too? Not only is it an opportunity to improve the look and feel and perceived usability, it will also help highlight the new content and features, and if done successfully, boost the chances of eliciting positive feedback from users and customers.

In conclusion, a request from a client for a re-skin should send up a red flag telling you to dig deeper and examine other hidden issues. Not only will this give more importance to your work, it could save your client a lot of time and money in the long run.

So, maybe you’re asking: how do you design for three different mobile platforms without losing your marbles?

Before starting on each project, I did my homework to see what other designers and developers have done in the space. For Android and Blackberry, this study was not only a nice-to-have, it was a requirement. While Apple has a reasonably good human interface guidelines to shepherd designers and developers through putting together a consistent and intuitive interface for iPhone users, the other two leave a lot to be desired.

Google, ironically, preaches the value of using consistent UI components without ever really sharing what those components might be to any great extent. They have an in-depth tutorial on how to create icons but don’t mention much on what the other standard UI components should look like. This leads designers to go off on their own and create what they think is right for the Android UI versus Google suggesting what the best practices are. This could easily be solved by providing a comprehensive style guide.

What’s the purpose of doing this? The purpose is to understand the personality, interaction and visual language of a platform so that the designer is able to design an interface that users already visually and interactively understand. The users understand and intuit this language based on previous experiences with the platform’s native apps and/or other downloaded apps. This is why an iPhone app should look and feel like an iPhone app and an Android app should look and feel like one of its own. Differentiation is important where there’s competition, but without any consistent use of native UI elements, the user is at a loss with the interface and has to learn something new costing them time, effort and frustration.

Some companies take the easy route. They simply take any graphics and user flows they created for one platform (typically the iPhone) and adapt it to the new one. Because of Android’s lack of support (and perhaps because of the developer’s lack of interest), we see a lot of this being applied to its apps. This is not only bad for Android’s effort to provide a consistently intuitive user experience but it’s also, in some cases, bad for the app itself which doesn’t utilize native elements and behaviors that ultimately, could create a better user experience particular to that platform.

So here’s the answer to the burning question:

Can you Android-ize an already existing iPhone app? Does one size fit all?

No, not without confusing the user with elements they’re unfamiliar with and possibly missing out on better ways to present a feature using the platform’s native standards.

In regard to user interaction design, there are some big differentiators between the three platforms. Here are some of the big ones:

Android and Blackberry platforms have menus

They both have hard keys on their physical devices that make it possible to bring up a menu and navigate to other options or shortcuts, the iPhone doesn’t. This helps in some circumstances, to hide what would normally be considered clutter. It allows designers to conceal additional features and functionality for when the user is ready to use them. It may make the user experience actually easier by requiring less taps or clicks.

They both have hard keys on their physical devices that make it possible to bring up a menu and navigate to other options or shortcuts, the iPhone doesn’t. This helps in some circumstances, to hide what would normally be considered clutter. It allows designers to conceal additional features and functionality for when the user is ready to use them. It may make the user experience actually easier by requiring less taps or clicks.

Android and Blackberry platforms have a back key

Same as above. This makes it easy to remove controls that would otherwise be necessary to go back.

Blackberry screens come in several different sizes

In my opinion, this is why Blackberry’s App World has a long, long way to go and may ultimately, fizzle out. Designing and developing an app that works on five different screen sizes is a headache. It requires a great deal of production and time from designers and developers and leads to too many compromises. In order to save time and money, the app’s design is required to be generic enough to work with all the various device models. To understand this better, check out Pandora’s Blackberry page.

Blackberry uses a trackball on most of its devices

This is yet another hindrance to Blackberry’s success in the app market. While trackballs work fine for scrolling through a list such as your email’s inbox, it’s cumbersome when it comes to navigating through the tabs of an app, especially if there are two sets, one at the top and one at the bottom. Unless there’s something I don’t know (Blackberry users?), a user must select all the screen’s components (tabs, buttons, fields, hyperlinks) on the way to navigating from one end of the screen to the other. There’s no way to fly from, lets say, the top-left tab to the bottom-right tab like you can do with a mouse or even better, your finger. Everything snaps to a grid and the trackball cursor must follow it. Needless to say, this is extremely cumbersome and requires that screens have few selectable components.

Pop-ups in Android are completely customizable

One nice work-around with Android is that pop-ups are completely customizable. This means in some cases you can use a pop-up interface rather than having to take the user to a new screen. Where would this be helpful? Any kind of detail screen where the user taps an element on the screen to learn more. The pop-up can be customized to have its own background, scrollbar, icons, etc. (caveat: Android pop-ups are not meant to be used like this, so it’s a bit of a hack from what I understand).

iPhone apps don’t use standard web browser form components

What, no radio buttons? No drop-downs? Nope. While web pages displayed on the iPhone do have these options, iPhone app interfaces don’t. Instead, they have switches, slot machine-like pickers and sliding knobs. This is a good thing—they thought about the new touchscreen technology and adapted the UI components to fit it. From a design point of view, this means that you will have to think of how to set up form components differently.

Needless to say, there are also many visual differences between these three platforms. Once you figure it out, Android actually has a pretty nice graphical user interface. Again, there biggest problem is not giving designers and developers enough guidance (i.e., this is what a progress bar looks like, this is what a standard OS button looks like, this is what a pop-up looks like, etc.). In return, their collection of apps appears somewhat clunky and doesn’t have the same cohesiveness that the iPhone’s apps do. This might not be such a big deal except for Android users never know what to expect and the constant use of iPhone-like components in Android apps (such as the ubiquitous shiny buttons) makes Android appear cheap. Android has some exceptional functionality, why not do the same with the UI standards? All it would require on their part, I believe, is a well-written user interface guide.

So, again, how do you design for three different mobile platforms without losing your marbles?

One at a time. Each version of the app will have the same list of key use cases but will require a fresh perspective when it comes down to user interaction and screen layouts. In some cases, like the Blackberry, you can’t squeeze a square peg in a round hole. You have to take it for what it is: a conventional mobile phone UI. Each platform has its own unique challenges and that’s half the fun of being a designer or developer.

Lastly, I’d like to speak directly to Apple, Google, Blackberry and Palm on behalf of all those who seek a better understanding of these interfaces and wish to design and develop a coherent user experience for these platforms. Just as you have given developers the tools to code your apps, you should give designer’s the tools to design your apps. Offer up layered Photoshop, Fireworks and Illustrator files of all your UI components just as this kind person has done for the iPhone and these people and these people. Why make it hard for everybody to put together an accurate representation of your interface? Give us the visual language so that we can, as designers, design useful and intuitive apps that contain the visual standards your users are already accustomed to. To Google’s credit, they do provide templates for creating menu icons, but offer little more for the designer. It would go a long way to not only provide an SDK but also a “software design kit”.