New UI designed from the ground up for tablets

Android 3.0 is a new version of the Android platform that is specifically optimized for devices with larger screen sizes, particularly tablets. It introduces a brand new, truly virtual and “holographic” UI design, as well as an elegant, content-focused interaction model.

 Android 3.0 builds on the things people love most about Android — refined multitasking, rich notifications, Home screen customization, widgets, and more — and transforms them with a vibrant, 3D experience and deeper interactivity, making them familiar but even better than before.
The new UI brings fresh paradigms for interaction, navigation, and customization and makes them available to all applications — even those built for earlier versions of the platform. Applications written for Android 3.0 are able to use an extended set of UI objects, powerful graphics, and media capabilities to engage users in new ways.
System Bar, for global status and notifications
Across the system and in all applications, users have quick access to notifications, system status, and soft navigation buttons in a System Bar, available at the bottom of the screen. The System Bar is always present and is a key touchpoint for users, but in a new "lights out mode" can also be dimmed for full-screen viewing, such as for videos.
Action Bar, for application control
In every application, users have access to contextual options, navigation, widgets, or other types of content in an Action Bar, displayed at the top of the screen. The Action Bar is always present when an application is in use, although its content, theme, and other properties are managed by the application rather than the system. The Action Bar is another key touchpoint for users, especially with action items and an overflow dropdown menu, which users frequently access in a similar manner in most applications

Customizable Home screens
Five customizable Home screens give users instant access to all parts of the system from any context. Each screen offers a large grid that maintains spatial arrangement in all orientations. Users can select and manipulate Home screen widgets, app shortcuts, and wallpapers using a dedicated visual layout mode. Visual cues and drop shadows improve visibility when adjusting the layout of shortcuts and widgets. Each Home screen also offers a familiar launcher for access to all installed applications, as well as a Search box for universal search of apps, contacts, media files, web content, and more.
Recent Apps, for easy visual multitasking
Multitasking is a key strength of Android and it is central to the Android 3.0 experience. As users launch applications to handle various tasks, they can use the Recent Apps list in the System Bar to see the tasks underway and quickly jump from one application context to another. To help users rapidly identify the task associated with each app, the list shows a snapshot of its actual state when the user last viewed it.

Redesigned keyboard

The Android soft keyboard is redesigned to make entering text fast and accurate on larger screen sizes. The keys are reshaped and repositioned for improved targeting, and new keys have been added, such as a Tab key, to provide richer and more efficient text input. Users can touch-hold keys to access menus of special characters and switch text/voice input modes from a button in the System Bar.

Improved text selection, copy and paste

When entering or viewing text, a new UI lets users quickly select a word by press-hold and then adjust the selection area as needed by dragging a set of bounding arrows to new positions. Users can then select an action from the Action Bar, such as copy to the clipboard, share, paste, web search, or find.

New connectivity options

Android 3.0 includes new connectivity features that add versatility and convenience for users. Built-in support for Media/Picture Transfer Protocol lets users instantly sync media files with a USB-connected camera or desktop computer, without needing to mount a USB mass-storage device. Users can also connect full keyboards over either USB or Bluetooth, for a familiar text-input environment. For improved wi-fi connectivity, a new combo scan reduces scan times across bands and filters. New support for Bluetooth tethering means that more types of devices can share the network connection of an Android-powered device.

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