App crashes but no crashlogs on the device

Our current beta version of the app crashes sometimes, this happens to myself and my colleagues. The beta's are send with Apple's TestFlight app and I build it to my own phone. Phones are iPhone6 running latest iOS8.

When I hook each of them on my mac and load the crashlogs I couldn't find any crashlogs on the time the crash has occurred (also none on other times). I see recent crashlogs of other apps but none of the crashes is our app. Also there isn't an unknown crash at that time indicating a memory issue.

The app crashes after using it a couple of minutes to a hour and seems not to crash each time. So not on startup but somewhere in the middle and not always in the middle. App is using the users-location actively.

Changes in this beta version: - More MKOverlays on the map - First time MKMapCamera to position the users location on the map - Crashes occur while using the map

Any ideas?

Best, Sjoerd

edit: After running the app on my phone in xcode for some time I finally found some crashlogs. Perhaps it's the kind of crash?:

Exception Type:  EXC_RESOURCE
Exception Subtype: WAKEUPS
Exception Message: (Limit 150/sec) Observed 300/sec over 300 secs
Triggered by Thread:  19

Seems that I had memory crashes at another time. Weird.

I ran the app on my own phone (not simulator) in debug and found out that is was a memory crash. Now the memory crashlog was there with the right time now

Not sure what happened before and why the time wasn't right.

Also memory crashlogs appear as unknown. See the first one: