At Google I/O 2011 today, the company made a bunch of Android announcements. First off, Android 3.1 (codenamed Honeycomb, just like Android 3.0) is now official, offering the following features for users and developers:

  • Open Accessory API. This new API provides a way for Android applications to integrate and interact with a wide range of accessories such as musical equipment, exercise equipment, robotics systems, and many others.
  • USB host API. On devices that support USB host mode, applications can now manage connected USB peripherals such as audio devices. input devices, communications devices, and more.
  • Input from mice, joysticks, and gamepads. Android 3.1 extends the input event system to support a variety of new input sources and motion events such as from mice, trackballs, joysticks, gamepads, and others.
  • Resizable Home screen widgets. Developers can now create Home screen widgets that are resizeable horizontally, vertically, or both.
  • Media Transfer Protocol (MTP) Applications can now receive notifications when external cameras are attached and removed, manage files and storage on those devices, and transfer files and metadata to and from them.
  • Real-time Transport Protocol (RTP) API for audio. Developers can directly manage on-demand or interactive data streaming to enable VOIP, push-to-talk, conferencing, and audio streaming.

The company also talked about its next version of Android, codenamed Ice Cream Sandwich, which is slated for Q4 2011. While we don't know what version number it will have, rumors have previously suggested Android 4.0. The big change with Ice Cream Sandwich will be that it works on all devices. That means Google will be porting features from Android 3.0 (codenamed Honeycomb) to the smartphone, including the holographic user interface, more multitasking, the new launcher, and richer widgets.

In addition to the OS updates, Google also shared more information about the Android ecosystem. Over the past two and a half years, the company has shipped eight releases of Android. There are now more than 310 Android devices around the world and 100 million activated Android devices so far.

Google also revealed that there are now 400,000 new Android devices activated every day. In December 2010, the company was activating 300,000 Android phones daily.

The search giant also noted there are 200,000 free and paid applications available in the Android Market, but we've known this since December 2010.

Last but not least, the company revealed there are 4.5 billion apps installed from the Android Market. That's impressive, because just last month we were at 3 billion installed apps. Because Android is open, the platform's users can download apps from more than one app store.