The iPhone is a line of touchscreen-based smartphones designed and marketed by Apple Inc. that use Apple's iOS mobile operating system. The first-generation iPhone was announced by Apple co-founder Steve Jobs on January 9, 2007. Since then Apple has annually released new iPhone models and iOS updates. As of November 1, 2018, more than 2.2 billion iPhones had been sold.
The iPhone's user interface is built around a multi-touch screen with a virtual keyboard. The iPhone connects to cellular networks or Wi-Fi, and can make calls, browse the web, take pictures, play music and send and receive emails and text messages. Since the iPhone's launch further features have been added, including larger screen sizes, shooting video, waterproofing and the ability to install third-party mobile apps through an app store, as well as accessibility support. Up to 2017, iPhones used a layout with a single button on the front panel that returns the user to the home screen. Since 2017, more expensive iPhone models have switched to a nearly bezel-less front screen design with app switching activated by gesture recognition.