Update: Draw Things uses “One-time photo selection” which according to Settings > Privacy & Security > Photos “Even if your photos were recently shown to you to select from, the app did not have access to your photo library.” Still, I didn’t realize apps could save to Photos without explicitly asking permission.
I don’t recall giving “Draw Things” permissions to access my photo library, yet the app is able to save to my photo library without prompting and able to read existing images.
I may have misunderstood what permissions apps should ask for when saving to the photo library.
I use PHPickerViewController: https://developer.apple.com/documentation/photokit/phpickerv... which runs out of the process such that when you want to select a photo into the app, I have no access to any information about your other photos and the location info is erased from what PHPickerViewController passed to me.
When save the photo, I only use UIImageWriteToSavedPhotosAlbum (https://developer.apple.com/documentation/uikit/1619125-uiim...) which asks you permission to write to the album, not read permission (they are separate). There are more things I can do if I have read permissions (like create a "Draw Things" collections and save to that, rather than save to generic Camera Roll). Ultimately decided to not do that because I don't want more permissions than I minimally absolutely need.
I don’t recall giving “Draw Things” permissions to access my photo library, yet the app is able to save to my photo library without prompting and able to read existing images.
I may have misunderstood what permissions apps should ask for when saving to the photo library.