Version – 3.0
Release date – February 22, 2011

Features

Optimized tablet support with a new “holographic” user interface (removed again the following year with version 4.2)
New easter egg, an image of a Tron-themed bumblebee
Added System Bar, featuring quick access to notifications, status, and soft navigation buttons, available at the bottom of the screen
Added Action Bar, giving access to contextual options, navigation, widgets, or other types of content at the top of the screen
Simplified multitasking – tapping Recent Applications in the System Bar allows users to see snapshots of the tasks underway and quickly jump from one application to another
Redesigned keyboard, making typing fast, efficient and accurate on larger screen sizes
Simplified, more intuitive copy/paste interface
Multiple browser tabs replacing browser windows, plus form auto-fill and a new “incognito” mode allowing anonymous browsing
Quick access to camera exposure, focus, flash, zoom, front-facing camera, time-lapse, and other camera features
Ability to view albums and other collections in full-screen mode in Gallery, with easy access to thumbnails for other photos
New two-pane Contacts UI and Fast Scroll to let users easily organize and locate contacts
New two-pane Email UI to make viewing and organizing messages more efficient, allowing users to select one or more messages
Hardware acceleration
Support for multi-core processors
Ability to encrypt all user data
HTTPS stack improved with Server Name Indication (SNI)
Filesystem in Userspace (FUSE; kernel module)
Disallows applications from having write access to secondary storage (memory cards on devices with internal primary storage) outside of designated, application-specific directories. Full access to primary internal storage is still allowed through a separate application-level permission.

UI refinements
Connectivity for USB accessories (USB On-The-Go).
Expanded Recent Applications list
Resizable Home screen widgets
Support for external keyboards and pointing devices
Support for joysticks and gamepads
Support for FLAC audio playback
High-performance Wi-Fi lock, maintaining high-performance Wi-Fi connections when device screen is off
Support for HTTP proxy for each connected Wi-Fi access point

Improved hardware support, including optimizations for a wider range of tablets
Increased ability of applications to access files on the SD card, e.g. for synchronization
Compatibility display mode for applications that have not been optimized for tablet screen resolutions
New display support functions, giving developers more control over display appearance on different Android devices