I'm currently in the process of reading the excellent "Lessons Learned in Software Testing: A Context-Driven Approach". Early on the following is mentioned.

Test common threats before exotic threats.

Seems reasonable enough. That said, it got me thinking It'd be cool to generate a list of such threats for future devs/testers to draw on. So...I'm calling on the collective experience of any Tilders involved in iOS or Android development to lend a hand.

In your time working on mobile, what issues have you encountered that you would you classify as exotic? I.e those issues that infrequently arise but when they do can cause major damage. Any and all help is appreciated.