Around 2015, My niece told me she worked at a bank teller and the first thing they did was require her to install the bank’s app and rate it five stars. She said her phone is too old and they got angry. And she’d tell me they’d do “phone sweeps” to see if the app was on people’s phones.

Do min-wage companies still do this or do they know better?

Personal devices are personal.

Nowhere in the civilized world are they allowed to do this.

yeah they are. if they pay your phone bill.
Still no in any civilized society.
it’s literally a contractual provision. are contracts not allowed in societies
Correct, some contracts cannot be done. Depending on the specifics, the illegal parts of the contract are unenforceable, or the entire thing is null and void. Employers often hate this, because it limits the exploitation they can enact upon employees.