#Proprietary, #NonFree, #Commercial, #ClosedSource iPhone and (maybe) Android apps which secretly siphon all data they can and sell it to Google and Facebook without the user ever noticing, much less consenting to it.

This is particularly tempting on iOS where it's very difficult to offer #FreeLibreOpenSourceSoftware because the Apple App Store makes it almost impossible to comply with certain #FreeSoftware licenses, and other app sources are basically illegal AFAIK.

On Android, one could say that apps on the Google Play Store are either also available on F-Droid or closed-source spyware that secretly hands your private data over to Google and Facebook.