Apple previewed the new watchOS 2 update to its Apple Watch software today at WWDC. It gives developers the ability to build faster and more powerful apps natively on Apple Watch, and lets them take advantage of hardware features like the Digital Crown, Taptic Engine, heart rate sensor, accelerometer and microphone.

New APIs let them enable audio and video playback and animation. Additionally, the ClockKit framework lets them represent their data as complications on the watch face.

“These new tools allow developers to make apps more robust,” the company says. “For example, Strava can more accurately track your heart rate while on a ride or run using data from the heart rate sensor and accelerometer; Insteon can give customers more precise controls to dim their lights or control the temperature with the Digital Crown; Volkswagen owners can get haptic feedback when their car door has been locked; WeChat includes audio messaging using the microphone; and Vine can host and play video right in the app.”

It includes new watch faces, anew new communication features for Mail, Friends, and Digital Touch.

“We are thrilled with the feedback we’re getting from Apple Watch customers, and after just a few weeks of availability we’re excited for developers to start building native apps for watchOS 2,” said Kevin Lynch, Apple’s vice president of Technology. “We think Apple Watch users will love being able to see information from their favorite apps right on the watch face, and enjoy the many new experiences developers will dream up now that they have access to even more innovative features of Apple Watch.”

Users can turn photos into a new watch face or view pictures from a photos app with every raise of the wrist. There’s a new time lapse watch face and a “time travel” feature that lets users scroll to see events in the future and past using the crown. This works for temperatures and info from third party apps like flight info.

There’s a new nightstand mode that lets you use Apple Watch as an alarm clock with the crown and side button serving as snooze and off buttons.

Merchant rewards and store-issud credit and debit cards for Apple Pay can be adde to Wallet, and there’s new support for Transit in Maps. There are also new workout capabilities from third-party apps and new Siri integration for workouts and launching Glances and reply to email.

Finally there’s a new Activation Lock.

The OS will be available to users in the fall as a free update.

Image via Apple