I’m nearing 25 000 rows in my app, and need to delete rows to get more space.
Yes, you can, but it won’t affect the rows used by the app. App: Logins is just a log of user logins. It’s not used by glide in any way. You could clear the whole thing and it wouldn’t affect anything in your app.
I should also add that 25,000 rows in a Pro app isn’t a hard limit. You should still be fine. I would be more concerned if things start to slow down later on.