iOS 1.0

Released: June 2007

Devices: iPhone 2G

Features: Core iOS UI, multitouch gestures, mobile safari, iPod, visual voicemail, maps, iTunes sync

iOS 2.0

Released: July 2008

Devices: iPhone 3G, iPhone 2G, iPod Touch 1st Gen

Features: Native 3rd-party apps, App Store, Microsoft Exchange support, MobileMe, contact search

iOS 3.0

Released: June 2009

Devices: iPhone 3GS, iPhone 3G, iPhone 2G, iPod Touch 2nd Gen, iPod Touch 1st Gen

Features: Cut, copy, paste, voice control, MMS, spotlight search, push notifications, USB & Bluetooth tethering, landscape keyboard, Find my iPhone

iOS 4.0

Released: June 2010

Devices: iPhone 4, iPhone 3GS, iPhone 3G, iPod Touch 3rd Gen, iPod Touch 2nd Gen

Features: Multitasking, home screen folders, FaceTime video chat, unified email inbox, threaded email messages, retina display support, iAd support

iOS 5.0

Released: October 2011

Devices: iPhone 4S, iPhone 4, iPhone 3GS, iPad, iPad 2, iPod Touch 4th Gen, iPod Touch 3rd Gen

Features: Siri, Notification Center, PC-free, iTunes Wi-Fi Sync, iMessage, iCloud

iOS 6.0

Released: Fall 2012

Devices: iPhone 5, iPhone 4S, iPhone 4, iPhone 3GS, iPad mini, iPad 4th Gen, iPad 3rd Gen, iPad 2, iPod Touch 4th Gen, iPod Touch 5th Gen

Features: Homegrown Maps and turn-by-turn navigation, Siri enhancements, Facebook integration, Passbook, iCloud Tabs, mail enhancements, FaceTime over cellular

iOS 7.0

Released: Fall 2013

Devices: iPhone 5s, iPhone 5c, iPhone 5, iPhone 4S, iPhone 4, iPad mini, iPad 4th Gen, iPad 3rd Gen, iPad 2, iPod Touch 5th Gen
Features: Visual overhaul, Control Center, AirDrop, refreshed core apps, iTunes Radios, FaceTime Audio