From The Apple Wiki

Short for Worldwide Developers Conference, WWDC is an expensive ($1000+) gathering for Mac and iPhone developers. It includes various sessions for developers as well, as a keynote to kick it all off. The keynote is public and available for download through the podcast "Apple Keynotes" (SD/HD/1080p) on iTunes. The developer sessions are semi-private and available with a free or paid Apple Developer account.

2008 Keynote

  • MobileMe announced and demonstrated
  • iPhone 3G announced and demonstrated
  • Push Notification Service for developers announced
  • Countries that the iPhone 3G was and still is planned to be released in announced

2009 Keynote

  • iPhone 3GS announced. A working model was not shown.
  • Push Notification Service announced for iPhone OS 3.0

2010 Keynote

2011 Keynote

2012 Keynote

  • iOS 6 announced.

2013 Keynote

  • iOS 7, New Mac Pro, MacBook Air and OS X Mavericks announced.

2014 Keynote

  • iOS 8, OS X Yosemite, and Swift announced.

2015 Keynote

  • iOS 9, OS X El Capitan, watchOS 2, and Swift 2 announced.

2016 Keynote

  • iOS 10, macOS 10.12, watchOS 3, and Swift 3 announced.