Which apps have Apple's thumbs up?
If I buy an app at the app store, does that mean Apple has made sure there's nothing creepy (like misuse of access to all my files) about the app?
iMac 21.5″, macOS 10.15
Question marked as
Yes. App Store apps need to follow privacy and functionality guidelines set forth by Apple. Apple reviews all apps submitted to the App store to comply with these guidelines.
By design, Apps needs to ask for your permission to access anything, and their descriptions in the App store need to disclose what types of access they require if any.
Obviously any files or data you choose to use with the App, will be accessible to the app, and in many cases to the developer if they are used by upload to the server for some reason. Its up to you ti trust the app with your data at that point.
You can see Apple's App Store submission Guidelines here: App Store Review Guidelines - Apple.com
From the Safety section: When people install an app from the App Store,
they want to feel confident that it’s safe to do so—that the app
doesn’t contain upsetting or offensive content, won’t damage their
device, and isn’t likely to cause physical harm from its use. We’ve
outlined the major pitfalls below, but if you’re looking to shock and
offend people, the App Store isn’t the right place for your app.