I am not sure how to generate device log if there isn’t a crash, but if I just look at the device output from Xcode, here is what I find odd on each tick event
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Feb 16 13:26:45 Shunxus-iPhone UE4Game[11036] <Notice>: [2018.02.16-21.26.45:703][170]LogScript: Warning: Accessed None trying to read property ARToolkit
ARToolkitSimple_C /Game/Maps/ARToolkitSimple.ARToolkitSimple:PersistentLevel.ARToolkitSimple_C_0
Function /Game/Maps/ARToolkitSimple.ARToolkitSimple_C:ExecuteUbergraph_ARToolkitSimple:01CA
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