IOS 5

iOS 5, Codenamed "Telluride", was the 5th major release of iOS designed and distributed by Apple for the iPhone, iPad, and iPod Touch. iOS 5 was released on 12 October 2011 and can be downloaded at iTunes.

New Features included but were not limited to:
 * Notification Center
 * iMessage
 * Newsstand
 * Reminders
 * Integration
 * Can play content while device is synching with iTunes
 * Group by Album Artist option in Music
 * Shortcut to Camera from Lockscreen
 * Able to flag emails
 * Reading List in Safari
 * Search within a web page (iPad 2 only)
 * Private Browsing
 * iCloud
 * PC Free
 * FaceTime without a SIM (iPhone only)
 * Siri (iPhone 4S only)
 * Hide keyboard (iPad only)
 * Tabbed Browsing (iPad only)

Trivia

 * Initial release on iPhone 4S
 * iPhone 3G and 2nd generation iPod Touch were not supported on this release
 * iPad (1st generation) and iPod touch (3rd generation) had limited support
 * iPhone 3GS, iPhone 4, iPhone 4S, iPod touch (4th generation), iPad 2 and iPad 3 were all fully supported
 * This Is The First IOS To Feature Music And Newsstand.
 * This Is The First Time To Introduce Siri.
 * This Is The First IOS To Feature Swipe Up To Camera.
 * This Is The Last IOS To Use The Original Settings Icon.

5.x.x Releases

 * iOS 5 (12 October 2011)
 * iOS 5.0.1 (10 November 2011)
 * iOS 5.1 (March 7, 2012)
 * iOS 5.1.1 (May 8, 2012)