Health and Fitness

Fitness apps can use workout sessions to remain in the foreground during an active workout. When time passes between wrist raises, Apple Watch normally reverts to displaying the watch face. When your app has an active workout session, Apple Watch displays your app instead of the watch face.

Workout sessions are solely for fitness apps and only when the user is in the middle of a workout. However, an active workout session does not guarantee that your app is displayed on wrist raise. If the user switches to another app, either by launching it from the Home screen or launching it from a notification interface, the workout session continues but the system returns to displaying the watch face.

Provide obvious controls to start and end workout sessions. Provide clear feedback that a workout started or ended when those controls are used.

Avoid placing workout controls solely on menus. Always provide controls in your main interface that clearly show how to end a workout session. You may also include controls in a menu as a secondary means to ending the session. You should similarly avoid menu actions as the sole way to start a workout session.

Make it clear that the user is in an active workout session. Design your interface to make it clear when a workout session is in progress. Use a different layout or a noticeably different appearance to indicate that your app is in a different mode. During subsequent wrist raises, the changed appearance should clearly remind the user your app is in a workout session.

Make text larger and more readable during a workout. The text in your workout interface should be easy to read while the user is in motion. Use larger font sizes and arrange text so that the most important information is obvious.

Provide confirmation about the end of a workout session. When the user ends a workout, display a confirmation that the workout ended and include feedback about what information was recorded.

Audio and Video

Apps can play short video and audio clips while the app is active and running in the foreground. You can embed clips directly in your interface using a movie element and play video inline or using a separate interface.

Apps can play longer audio-only content through a connected Bluetooth headset when the app is inactive. Long audio clips are played in the background and are intended for apps that play music, audio books, or other long forms of audio content. Your app initiates audio playback but the system manages it.

Keep foreground audio and video clips short. The media clips in your app’s interface should be no more than 30 seconds, and shorter is preferred. Long clips consume more disk space and require users to keep their wrists raised for longer periods of time, which can cause fatigue.

Use the previous end time when resuming playback of a long audio or video clip. Resuming playback at the previous stopping point lets the user quickly continue where they left off.

Use the proper encoding values for media assets. The following table lists the recommended encoding values for audio and video assets. The audio encoding values apply both to movies and audio-only assets.

Video codec H.264 High Profile
Video bit rate 160 kbps at up to 30 fps
Resolution (fullscreen) 208px × 260px (portrait orientation)
Resolution (16:9) 320px × 180px (landscape orientation)
Audio 32 kbps stereo


HomeKit lets people securely control connected accessories in their homes, such as locks, lights, shades, cameras, garage doors, sensors, and thermostats, from their Apple Watch. These accessories communicate with iCloud or a server to receive instructions and provide status updates. This communication can take place directly or through a device in the home that operates as a hub, such as Apple TV or iPad.