[sciurius]

You have my vote for an update feature in this case (same title/same source). I think it's too much to have an "intelligent" update feature with comparing fields. It should be sufficient if the old metadata is overwritten with the data of the update cvs.

FWIW, my MSPro-Tools on GitHub include get_meta and put_meta tools. Get_meta produces a JSON file that contains most of the metadata. You can modify it, and use put_meta to update the database.
You still have to (manually) transfer the database from the tablet to the PC and vice versa. And of course you risk losing everything .

https://github.com/sciurius/MSPro-Tools