Am interested to know if anyone else can replicate this crash.
I have an app that has a timer constantly running (every so often it checks online and downloads something).
If I run it from within AppPlayer on my iPhone it works fine, but then if I exit my app and return to the main AppStudio Player screen (where all the app icons are etc), the entire AppStudio Player crashes.
It's not a huge problem, just an annoyance as I have to open the Player back up again each time.
If someone else could replicate then I might lodge it as a bug report with ESRI.