In addition, iOS 5.1 features Japanese language support for Siri, though Apple has warned that availability may be limited during the initial roll-out. The update can be downloaded through the "Software Update" option found in the Settings application on an iOS device with iOS 5 or later.
The update has a number of changes to the camera application, with face detection now highlighting all detected faces in a frame. The camera app for iPad has also been given a redesign.
The full list of features in iOS 5.1, according to Apple, are:
Japanese language support for Siri (availability may be limited during initial rollout)
Photos can now be deleted from Photo Stream
Camera shortcut now always visible on Lock Screen for iPhone 4S, iPhone 4, iPhone 3GS and iPod touch (4th generation)
Camera face detection now highlights all detected faces
Redesigned Camera app for iPad
Genius Mixes and Genius playlists for iTunes Match subscribers
Audio for TV shows and movies on iPad optimized to sound louder and clearer
Podcast controls for playback speed and a 30 second rewind for iPad
Updated AT&T network indicator
Addresses bugs affecting battery life
Fixes an issue that occasionally caused audio to drop for outgoing calls
[ View article on AppleInsider ]