Sascha, if I were to reinstall the app right now, I would back up the data inside the djay folder (open the Files app, go to „On my iPhone“) and reinstate that once the reinstall finished. My hope (not checked) would be that this saves all metadata.
I recently reinstalled and did not make a backup since I relied on the iCloud backup. iCloud backup is potentially broken right now (see here: iCloud not syncing - #16 by djjoejoe) but even with iCloud intact, you will lose beat grids and BPMs, plus your individual settings. It’s a hassle, frankly.
