ActivityKit

ActivityKit owns real-time, glanceable Live Activities displayed on the Lock Screen and Dynamic Island. Ordinary timeline widgets belong in widgetkit, and generic APNs setup belongs in push-notifications; ActivityKit owns the Live Activity lifecycle and payload contract. aps.content-state must decode into the exact ActivityAttributes.ContentState shape, including any coordinated custom date/range encoding. Modern ActivityContent lifecycle examples require iOS 16.2+ unless noted.

See references/activitykit-patterns.md for complete code patterns including push payload formats, concurrent activities, state observation, and testing.

Contents

• Workflow
• ActivityAttributes Definition
• Activity Lifecycle
• Lock Screen Presentation
• Dynamic Island
• Push-to-Update
• Recent Additions
• Common Mistakes
• Review Checklist
• References

Workflow

1. Create a new Live Activity

1. Verify the host app capability and NSSupportsLiveActivities = YES.
2. Define ActivityAttributes.ContentState; encode and decode a representative fixture that matches the server payload contract.
3. Create ActivityConfiguration and preview Lock Screen and Dynamic Island states, including stale and terminal content.
4. Check ActivityAuthorizationInfo.areActivitiesEnabled, then request and observe the activity lifecycle.
5. Exercise local update and every terminal end path.
6. For remote updates, validate a complete reference payload before registering rotating update or push-to-start tokens with the server.

2. Review existing Live Activity code

Run through the Review Checklist at the end of this document.

ActivityAttributes Definition