If we simply mandated that everyone install an app on their phone so that the government can track them scales very well. The people without the app would probably be criminals,
I don't follow that... posting a police officer in everyone's house is pretty much a Third and Fourth Amendment violation and not primarily constrained by finances.
Define criminal ? In the USA Under laws like the Fugitive Slave Act of 1793 and 1850, an enslaved human who escaped was considered a criminal.
Sheltering humans running away from slavery was also a crime .
It was illegal for black Americans to learn to read and write. Seeking education made them a criminal.
Buying or selling a beer made you a criminal during prohibition.
Do you see how easy it is to make someone a criminal?