Apple is rolling out the third watchOS 3.2 beta for developer testing on Apple Watch. watchOS 3.2 beta includes Theater Mode which disables raise-to-wake and mutes alerts.
Apple is also introducing SiriKit to Apple Watch with watchOS 3.2 beta. SiriKit lets developers integrate their apps with Siri for select uses. Prior to watchOS 3.2 beta, SiriKit was limited to iOS apps.
As for Theater Mode, this is how Apple describes the new feature:
Theater Mode lets users quickly mute the sound on their Apple Watch and avoid waking the screen on wrist raise. Users still receive notifications (including haptics) while in Theater Mode, which they can view by tapping the screen or pressing the Digital Crown.
And here’s how Theater Mode looks on Apple Watch: