The iPad runs on iPadOS. Prior to the introduction of iPadOS in 2019, the iPad ran iOS, which was created for the iPhone and iPod Touch. The first iPad was released in 2010. Although built on the same underlying Unix implementation as macOS, its user interface is radically different. iPadOS is designed for touch input from the user's fingers and has none of the features that required a stylus on earlier tablets. Apple introduced multi-touch gestures, such as moving two fingers apart or together to zoom in or out, also termed "pinch to zoom". iPadOS and iOS are built for the ARM architecture.