App shutdowns on IOS

[APOS80]

Device: IPhone 15 Pro
App: RTab-Map

The app often shuts down without warning while scanning, normally when over 2gb usage.

I also suggest a mode for just collecting data for post processing.

[matlabbe]

Note that you can recover your scan after a crash. Look under RTAB-Map folder in your File Explorer and backup rtabmap.tmp.db file somewhere. Using desktop computer, it is possible to recover it with:

rtabmap-recovery my_corrupted_map.db

For a low RAM recording mode, it is a new feature we want to add in the future #1320