How to actually read an iOS crash log
Exception types, the crashed thread, symbolication, and the two entries in the crash list that are not crashes at all.
"It only happens on that one phone"
A checklist for bugs that reproduce on only one device: iOS version, storage, temperature, battery health, profiles and settings people forget to check.
What is actually inside an iOS app sandbox
Documents, Library, Caches and tmp. What iOS backs up, what it deletes without notice, and why "the cache will not clear" is usually a directory choice.
A real-device QA workflow that produces reproducible tickets
What to capture while a bug is happening, so the ticket contains evidence instead of a description: logs, timings, device state and screenshots.