In Poland, people who have been told to self-isolate because of being in contact with someone who has Covid or as a result of coming into the country, have to install an app on their smartphones which was developed in a few days back in March last year, and was made compulsory on April 1st.
You are contacted at random intervals, sometimes several times a day, and have 20 minutes to respond by sending a photo of your face. The photo is matched to one taken either from your passport or taken at the time you are told to self-isolate, and is used with geolocation to confirm that you are where you are supposed to be. If you don't respond withng the 20 minutes, you get a visit from the police to check up on you.
The contacting, photo matching and location checking are automated, which means you don't need vast numbers of staff to do the checking.
The only people excused from installing the app are those who are blind, visually impaired or who have signed a declaration that they do not use telecommunications or have a smartphone, and there is a hefty fine for those who don't install and use the app.
Still, I suppose that such a relatively simple and straightforward method of checking on people who are supposed to self-isolate isn't seen as being appropriate here.