It's been almost seven years since the release of the first version of iOS on the original iPhone, and a lot has changed with each subsequent update. Join us as we take a tour of the highlights of how Apple's mobile OS has changed since 2007.
1 of 37 Apple's iOS mobile operating system is now almost 7 years old, and it continues to evolve every few months. With WWDC just a month away, here's a look back at the major releases since iOS 3 and the biggest features that each update introduced. Editors' note: This gallery was updated May 7, 2014.