On 20 May 2010, the Android 2.2 (Froyo) SDK was released, based on Linux kernel 2.6.32. Its features included:
- Speed, memory, and performance optimizations
- Additional application speed improvements, implemented through JIT compilation
- Support for the Android Cloud to Device Messaging (C2DM) service, enabling push notifications
- Improved Microsoft Exchange support, including security policies, auto-discovery, GAL look-up, calendar synchronization and remote wipe
- Improved application launcher with shortcuts to Phone and Browser applications
- USB tethering and Wi-Fi hotspot functionality
- Added an option to disable data access over mobile network
- Updated Market application with batch and automatic update features
- Quick switching between multiple keyboard languages and their dictionaries
- Voice dialing and contact sharing over Bluetooth
- Support for numeric and alphanumeric passwords
- Support for file upload fields in the Browser application
- Support for installing applications to the expandable memory
- Adobe Flash support
- Support for extra-high-PPI screens (320 ppi), such as 4" 720p
The Android 2.2.1 update was released on 18 January 2011, and included a number of bug fixes, security updates, and performance improvements.
The Android 2.2.2 update was released on 22 January 2011, and fixed minor bugs, including SMS rooting issues that affected the Nexus One.
The Android 2.2.3 update was released on 21 November 2011, and consisted of two security patches.