A manula update is available on Motorola ATRiX 4G user on the Motorola Update page you can download by visiting this link

Android 2.3 (Gingerbread), Version 4.5.91 Release Notes is available at this link.

Some of improvement are in this update

Enhancements to the picture Gallery allow you to aggregate all your photos, your

friends’ photos and photo comments from social networking and photo sites like 
Facebook and Picasa in one place for easy viewing

Enhancements so your Music player is now connected to a dashboard for music 
discovery. Plus, easy access to all your favorite artists, live, personalized 
recommendations for songs & videos and news and event updates

Updated user interface with simpler home screen design, including shift to use of white 
backgrounds in menus, enabling better viewing experience

Enhancement that enables easy access to favorite apps at bottom of each screen

Enhancement that helps you personalize and categorize favorite apps into groups so you 
can be more efficient

Enhancement that provides access to social content in one place so you can find out 
what is happening around you.  You can use Yelp reviews and Facebook check-ins to 
find out what others are recommending

You can now install any app you’d like, including the Amazon App store

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