watchOS 2 is the first major software update for the Apple Watch, and it will bring with it a plethora of APIs for developers to take advantage of. The APIs will allow developers to make use of the Force Touch feature on the watch, the Taptic Engine, allow them to write apps that can natively run on the smartwatch, and provide direct access to an array of sensors like the heart rate, microphone, and accelerometer on the smartwatch. Ultimately, these APIs will allow developers to create more feature rich apps for the smartwatch, thereby further enriching the experience of using it.
The biggest change ushered in by watchOS 2 is laying the groundwork for native apps that execute on the device itself, as opposed to being streamed wirelessly off an iPhone, which contributes to lagginess and poor performance.
If you are already running watchOS 2 beta 3 on your Apple Watch, you can grab the latest beta of the OS by using the Apple Watch app on your iPhone. If this will be the first beta build of the OS that you will be installing on your Apple Watch, make sure that your iPhone is also running on a beta build of iOS 9.
