Google today delivered an updated set of tools to Android app writers. It published the latest preview images of Android 5.0 Lollipop for the Nexus 5 smartphone and Nexus 7 tablets, as well as released the Android 5.0 SDK. With these tools, developers have all they need to get their apps up to speed.
Google made early versions of both Android 5.0 and the SDK available in June. Now, with Android 5.0's commercial release just several weeks away, it's time to get your apps in shape.
The first thing you'll need is the preview image of whichever device you're using for testing purposes. Right now, the preview images are for the Nexus 5, the Wi-Fi-only version of the 2013 Nexus 7, the ADT-1 and the Android emulator. The preview images are nearly finished versions of Android 5.0 Lollipop and shouldn't differ much — if at all — from the version that's going to be sent to consumers in the weeks ahead. Developers will need to download the appropriate images (here) and flash the OS directly to their devices. Use these directions if you're not familiar with the process.
Google plans to ship two new devices in early November with Android 5.0 preinstalled: the Nexus 6 smartphone and the Nexus 9 tablet. The phone is made by Motorola, while the tablet is made by HTC. Developers will be able to test their apps against these new devices, but not for several weeks at best. If you want your app to be Android 5.0-compliant at launch, you need to use the Nexus 5 or Nexus 7.
The Android 5.0 SDK is available for download here. It includes updated tools and new developer system images for testing. Developers can test against the latest Android platform using API level 21 and take advantage of the updated support library to implement Material Design, as well as the leanback user interface for Android TV apps.
The download includes the Android 5.0 SDK Platform & Tools; Android 5.0 emulator system image (32 bit and 64 bit); Android 5.0 emulator system image for Android TV (32 bit); Android v7 appcompat Support Library for Material Design theme backward capability; and Android v17 leanback library for Android TV app support.
Google recommends that developers recompile their apps against the Android 5.0 SDK, especially if any preview APIs were used in early development. Google warns that the APIs have changed between the preview SDK and the final SDK. Developers should validate their current Android apps in the new API 21 level with the ART (Android RunTime) enabled.
Aside from an incredible array of new APIs, Android 5.0 makes a significant change to the look and feel of the operating system. Google calls this Material Design. Google says Material Design lets apps use new colors and designs, while still adhering to some core design principles.
Google says Nov. 3 is the drop date for the Nexus 9 and Android 5.0's general availability. It is encouraging all developers to be sure their apps function properly in Android 5.0. The above tools will help developers do just that.