New in Android

Notifications have received some notable enhancements in Android 4.1:

• Users can act on notifications immediately from the drawer
• Notifications are more flexible in size and layout
• A priority flag helps sort notifications by importance
• Notifications can be collapsed and expanded

The base notification layout has not changed, so app notifications designed for versions earlier than Jelly Bean still look and work the same. Check the updated Notifications page for more details.

Widgets are an essential aspect of home screen customization, allowing "at-a-glance" views of an app's most important data and functionality right from the user's home screen. Android 4.1 introduces improved App Widgets that can automatically resize and load different content based upon a number of factors including:

• Where the user drops them on the home screen
• The size to which the user expands them
• The amount of room available on the home screen

You can supply separate landscape and portrait layouts for your widgets, which the system inflates as appropriate when the screen orientation changes. The Application Widgets has useful details about widget types, limitations, and design considerations.

One of Android's missions is to organize the world's information and make it universally accessible and useful. Our mission applies to all users-including people with disabilities such as visual impairment, color deficiency, hearing loss, and limited dexterity.

The new Accessibility page provides details on how to design your app to be as accessible as possible by:

• Making navigation intuitive
• Using recommended touch target sizes
• Labeling visual UI elements meaningfully
• Providing alternatives to affordances that time out
• Using standard framework controls or enable TalkBack for custom controls
• Trying it out yourself

You can supply separate landscape and portrait layouts for your widgets, which the system inflates as appropriate when the screen orientation changes. The Widgets page has useful details about widget types, limitations, and design considerations.

Android 4.0 removes the need for traditional hardware keys on phones by replacing them with a virtual navigation bar that houses the Back, Home and Recents buttons. Read the Compatibility pattern to learn how the OS adapts to phones with hardware buttons and how pre-Android 3.0 apps that rely on menu keys are supported.

The action bar is the most important structural element of an Android app. It provides consistent navigation across the platform and allows your app to surface actions.

Creating apps that scale well across different form factors and screen sizes is important in the Android world. Multi-pane layouts allow you to combine different activities that show separately on smaller devices into richer compound views for tablets.

The long press gesture which was traditionally used to show contextual actions for objects is now used for data selection. When selecting data, contextual action bars allow you to surface actions.