The iPhone is a mobile phone with Wi-Fi made by Apple. It does many things that a computer can do, but is small enough to fit in someone's hand. It is a mobile phone, meaning that it makes calls without wires. It can access the Internet as well. Like an iPod, it plays music and videos that have been put on it from a big computer, which is called syncing. It also has a calendar and camera, and can send text messages. People use the iPhone by touching the screen with a finger or two. This is done by tapping, dragging, and even typing on a keyboard shown on the screen. The first-generation iPhone can run iPhone OS 3.1.3, the iPhone 3G can run iOS 4.2.1, and the iPhone 3GS can run iOS 6.1.6. The iPhone 4S and later can run the newest version of iOS, iOS 8.