Best Practices for Honeycomb and Tablets

The first tablets running Android 3.0 (“Honeycomb”) will be hitting the streets on Thursday Feb. 24th, and we’ve just posted the full SDK release. We encourage you to test your applications on the new platform, using a tablet-size AVD.

Developers who’ve followed the Android Framework’s guidelines and best practices will find their apps work well on Android 3.0. This purpose of this post is to provide reminders of and links to those best practices.

Moving Toward Honeycomb

There’s a comprehensive discussion of how to work with the new release in Optimizing Apps for Android 3.0. The discussion includes the use of the emulator; most developers, who don’t have an Android tablet yet, should use it to test and update their apps for Honeycomb.

While your existing apps should work well, developers also have the option to improve their apps’ look and feel on Android 3.0 by using Honeycomb features; for example, see The Android 3.0 Fragments API. We’ll have more on that in this space, but in the meantime we recommend reading Strategies for Honeycomb and Backwards Compatibility for advice on adding Honeycomb polish to existing apps.

Specifying Features

There have been reports of apps not showing up in Android Market on tablets. Usually, this is because your application manifest has something like this:

Many of the tablet devices aren’t phones, and thus Android Market assumes the app is not compatible. See the documentation of . However, such an app’s use of the telephony APIs might well be optional, in which case it should be available on tablets. There’s a discussion of how to accomplish this in Future-Proofing Your App and The Five Steps to Future Hardware Happiness.


The new environment is different from what we’re used to in two respects. First, you can hold the devices with any of the four sides up and Honeycomb manages the rotation properly. In previous versions, often only two of the four orientations were supported, and there are apps out there that relied on this in ways that will break them on Honeycomb. If you want to stay out of rotation trouble, One Screen Turn Deserves Another covers the issues.

The second big difference doesn’t have anything to do with software; it’s that a lot of people are going to hold these things horizontal (in “landscape mode”) nearly all the time. We’ve seen a few apps that have a buggy assumption that they’re starting out in portrait mode, and others that lock certain screens into portrait or landscape but really shouldn’t.

A Note for Game Developers

A tablet can probably provide a better game experience for your users than any handset can. Bigger is better. It’s going to cost you a little more work than developers of business apps, because quite likely you’ll want to rework your graphical assets for the big screen.

There’s another issue that’s important to game developers: Texture Formats. Read about this in Game Development for Android: A Quick Primer, in the section labeled “Step Three: Carefully Design the Best Game Ever”.

We’ve also added a convenient way to filter applications in Android Market based on the texture formats they support; see the documentation of for more details.

Happy Coding

Once you’ve held one of the new tablets in your hands, you’ll want to have your app not just running on it (which it probably already does), but expanding minds on the expanded screen. Have fun!

Android 3.0 Platform Preview and Updated SDK Tools

Android 3.0 (Honeycomb) is a new version of the Android platform that is designed from the ground up for devices with larger screen sizes, particularly tablets. It introduces a new “holographic” UI theme and an interaction model that builds on the things people love about Android — multitasking, notifications, widgets, and others — and adds many new features as well.

Besides the user-facing features it offers, Android 3.0 is also specifically designed to give developers the tools and capabilities they need to create great applications for tablets and similar devices, together with the flexibility to adapt existing apps to the new UI while maintaining compatibility with earlier platform versions and other form-factors.

Today, we are releasing a preview of the Android 3.0 SDK, with non-final APIs and system image, to allow developers to start testing their existing applications on the tablet form-factor and begin getting familiar with the new UI patterns, APIs, and capabilties that will be available in Android 3.0.

Here are some of the highlights:

UI framework for creating great apps for larger screen devices: Developers can use a new UI components, new themes, richer widgets and notifications, drag and drop, and other new features to create rich and engaging apps for users on larger screen devices.

High-performance 2D and 3D graphics: A new property-based animation framework lets developers add great visual effects to their apps. A built-in GL renderer lets developers request hardware-acceleration of common 2D rendering operations in their apps, across the entire app or only in specific activities or views. For adding rich 3D scenes, developers take advantage of a new 3D graphics engine called Renderscript.

Support for multicore processor architectures: Android 3.0 is optimized to run on either single- or dual-core processors, so that applications run with the best possible performance.

Rich multimedia: New multimedia features such as HTTP Live streaming support, a pluggable DRM framework, and easy media file transfer through MTP/PTP, give developers new ways to bring rich content to users.

New types of connectivity: New APIs for Bluetooth A2DP and HSP let applications offer audio streaming and headset control. Support for Bluetooth insecure socket connection lets applications connect to simple devices that may not have a user interface.

Enhancements for enterprise: New administrative policies, such as for encrypted storage and password expiration, help enterprise administrators manage devices more effectively.

For an complete overview of the new user and developer features, see the Android 3.0 Platform Highlights.

Additionally, we are releasing updates to our SDK Tools (r9), NDK (r5b), and ADT Plugin for Eclipse (9.0.0). Key features include:

  • UI Builder improvements in the ADT Plugin:
    • Improved drag-and-drop in the editor, with better support for included layouts.
    • In-editor preview of objects animated with the new animation framework.
    • Visualization of UI based on any version of the platform. independent of project target. Improved rendering, with better support for custom views.

To find out how to get started developing or testing applications using the Android 3.0 Preview SDK, see the Preview SDK Introduction. Details about the changes in the latest versions of the tools are available on the SDK Tools, the ADT Plugin, and NDK pages on the site.

Note that applications developed with the Android 3.0 Platform Preview cannot be published on Android Market. We’ll be releasing a final SDK in the weeks ahead that you can use to build and publish applications for Android 3.0.