IPhone OS 2 available to the iPhone and iPod Touch. Prior to the public release of iPhone OS 2.0, Apple held a keynote event to announce the iPhone OS Software Development Kit ("SDK") to developers. The most notable feature of iPhone OS 2 was the App Store. Before this feature was introduced, the only way to install custom applications on the device was via jailbreaking, which is strongly discouraged and unsupported by Apple. There were 500 applications available for download at the launch of the App Store, though this amount has grown dramatically since then. Now, the App Store has more than 2
IPhone 5S iOS 7 and OS X Yosemite (version 10.10) noticeably departs from skeuomorphic elements such as green felt in Game Center, wood in Newsstand, and leather in Calendar, in favor of flat, colorful design. iOS 7 adds AirDrop, an ad-hoc Wi-Fi sharing platform. Users can share files with the iPhone 5 onwards, the iPod Touch (5th generation), iPad (4th generation) onwards, or iPad Mini (1st generation) onwards. The operating system also adds Control Center, a control panel accessed by swiping up from the bottom of the screen. Control Center contains a number of commonly used functions, such as volume and brightness