When I tried to open QuickCapture on an iPad Mini (5th gen) version 14.7.1 this morning, it would hit the splash screen then close after a few seconds. There were no logs recorded as far as I could tell. I tried restarting the iPad to no avail. The iPad had been updated last week, and I do not believe I used QuickCapture between the system update and today. It was crashing before and after I applied the August 2021 update. I had made no changes to any QuickCapture projects.
To resolve I reinstalled QuickCapture.
edit: as AndrewDeLuca pointed out in a comment, this is not a permanent fix. I was able to use it for over an hour without issue, but it started crashing again.