After unveiling what new features are coming to iOS 9 this fall, Apple said it will introduce a public beta this July, which is a first for the company. Well, for iOS; Apple offered a public beta of OS X 10.10. The really good news is that iOS 9 will support all of the devices running iOS 8, from the iPhone 6 Plus all the way down to the iPhone 4s. The developer beta, meanwhile, will be available starting today.