I have good success reading in data from a Google Sheets data source in Thunkable X. Thank you for that very useful feature!
I’m wondering if a user can tell the app what Google Sheet to read data from. So, for instance, Joe User uses some widget to tell the app to open a Sheet from his Google Drive, and Sue Otheruser can open a Sheet from her Google Drive, and so on. Is there a way to do this?
I second this question. That way Joe user controls his/her data without other users seeing it.
Yes. Use the google sheet app.
As far as using this as a database, you should have some way to link the user to any given record. Most commonly this will. Be the Firebase userID. That would be a field in the table. The. You filter any records not pertaining to that user in the search and retrieval phase.
(Sigh. Tried to edit and accidentally withdrew instead.)
I’ve been thinking about my question some this week, trying to figure out how to execute a project where it might make sense to read a bunch of data from an existing user-owned google sheet. Yes, I know, it’s a weird case, but I’m thinking about importing from a google sheet (user-specified) into the app, so maybe it sort of makes sense. I’m not proposing to store each user’s app-generated data in a different sheet. That’d be silly. 
But as the user, I’d much rather tell the app where to slurp the data from than retype it on my phone, for sure!
There is a Google sheets API, and Thunkable can make an API call. I suspect that means the answer to my question is yes, but you’d have to do a lot of work to make it happen, rather than just adding a data source and using the built in data source blocks. Maybe that’s not worth it.
I haven’t found way to programmatically add a data source using the built-in blocks (without making API calls and parsing json), but if I’m wrong, I’d like to know!