Description
When starting Live Activities via ActivityKit push notifications, the “start” notification is received correctly on iPhone 16 Pro Max, but subsequent update or end push notifications are not. The same implementation on iPhone 16 Pro behaves as expected (both start and update/end notifications are delivered and processed).
Environment Property Value
- Device (failing) iPhone 16 Pro Max
- Device (working) iPhone 16 Pro
- iOS Version 18.5
- Xcode / SDK 16.2/ActivityKit / Push Notifications
- Network Wi-Fi / Cellular (both tested)
Data Collection Method
- Devices connected via USB.
- Logs captured using Console.app.
- Log filtering applied for the liveactivitiesd daemon to isolate Live Activity behavior.
Initial Triage/Observations
- Payload format confirmed compatible; no incompatible fields.
- APNs token remains the same across messages (no refresh).
- Identical ActivityKit subscriptions/participants on both devices.
- Server-side delivery is confirmed: iPhone 16 Pro receives all messages (start, update, end).
- Only iPhone 16 Pro Max fails to receive update or end push notifications.
Log Analysis
iPhone 16 Pro (Working)
Push-to-Start successfully received:
13:45:20 - APSXPCDeliverMessageEvent: Created APSIncomingMessage
13:45:20 - Received message: eventType: start(SessionPushNotifications.IncomingMessage.EventType.StartParameters(attributesType:
"AchToLSUpgradeAttributes", attributesData: 125 bytes, inputs: []))
13:45:20 - Created activity: 1C081AC5-01AE-4EC0-8B67-5F2A9FAE2D60
13:45:45 - APSXPCDeliverMessageEvent: Created APSIncomingMessage
13:45:45 - Received message: eventType: end(dismissDate:
Optional(2025-07-21 21:00:44 +0000))
13:45:20 - Activity updated: 1C081AC5-01AE-4EC0-8B67-5F2A9FAE2D60
13:45:20 - Local activity did update: 1C081AC5-01AE-4EC0-8B67-5F2A9FAE2D60
iPhone 16 Pro Max (Failing)
13:56:39 - APSXPCDeliverMessageEvent: Created APSIncomingMessage
13:56:39 - Received message: eventType: start(SessionPushNotifications.IncomingMessage.EventType.StartParameters(attributesType:
"AchToLSUpgradeAttributes", attributesData: 125 bytes, inputs: []))
13:56:39 - Created activity: E6BBF691-0C7A-4791-98D2-6F1440D9932E
**No subsequent APNs push-to-update or push-to-end messages received.**
13:56:39 - No destinations for event E6BBF691... of type start
13:56:40 - No destinations for event E6BBF691... of type update
Questions for Apple Engineering
- Are there known issues with ActivityKit push notifications specifically on iPhone 16 Pro Max devices?
- What additional diagnostic logs (system, APNs, liveactivitiesd) would be most helpful to collect?
- Could device-specific power management, notification settings, or OS-level changes on Pro Max models affect Live Activity updates?
- Are there differences in how Live Activity push subscriptions or routing are handled on iPhone 16 Pro Max vs Pro that could lead to this issue?