How often did someone take you up on the offer?

I still am, but nobody dresses emo anymore. :(

They absolutely can, though. So many apps are secretly sending anything and everything you do in the app to 3rd parties without your knowledge. Use a firewall app that has logging and you’ll see what I mean. NetGuard is a good one for Android. (Don’t know of any for iOS cause I don’t own any Apple products, but I’m sure they’re out there.) Most major apps are selling you off to Facebook, for example. (Spotify does it.)

At least with with a browser, you can increase your privacy settings to block trackers, and use addons like UBlock Origin and NoScript. With an app they can do whatever they want with your data without you even knowing it.