IOS 5.1.1 release ( phiên bản chính thức)

iPad 1: 5.1.1

iPad 2 (GSM): 5.1.1

iPad 2 (CDMA): 5.1.1,

iPad 2: 5.1.1

iPad 3 (GSM): 5.1.1

iPad 3 (CDMA): 5.1.1

iPad 3 (wifi): 5.1.1

iPhone 4S: 5.1.1

iPhone 4 (GSM): 5.1.1

iPhone 4 (CDMA): 5.1.1

iPhone 3GS: 5.1.1

iPod touch 4G: 5.1.1,

iPod touch 3G: 5.1.1

iOS 5.1.1 is out: fixes iPad network switching, Safari syncing, AirPlay, HDR

According to release notes accompanying the update, it contains the obligatory improvements and bug fixes, including:
• Improves reliability of using HDR option for photos taken using the Lock Screen shortcut
• Addresses bugs that could prevent the new iPad from switching between 2G and 3G networks
• Fixes bugs that affected AirPlay video playback in some circumstances
• Improved reliability for syncing Safari bookmarks and Reading List
• Fixes an issue where ‘Unable to purchase’ alert could be displayed after successful purchase