Copenhagen (among other places) has a pretty convenient app-based model for parking. You use one of a few competing apps on your phone and enter your car's registration plate. When you park you open the app and it pulls location and starts a timer. You pick an amount of time you'll be parked but the apps I've used have reminders and you can trivially extend parking as you feel appropriate.
When you get back in your car you open the app and 'stop parking' and the app calculates the cost of the time you were parked (taking into account varying overnight and congestion zone rates). At the end of the month you get billed for that month's charges. You can also have multiple personas if you have a work vehicle/card.
In parts of south Florida there's a somewhat similar system where there's only one app you can use and money is taken immediately for the duration of the time you choose (with a small service fee included, of course). If you move your car before the expiration of your purchased time, you lose that value unless you repark in the same area [1]. The similarity is that the app will remind you that your parking is going to expire soon and you can simply extend (and pay that small service fee again, of course). I've seen this prepay-via-app model at various private parking facilities in other US cities as well.
[1]: The system uses number codes for what area you're parked in so you don't need to have location services necessarily (e.g. parking garage) with the code changing every couple streets.
When you get back in your car you open the app and 'stop parking' and the app calculates the cost of the time you were parked (taking into account varying overnight and congestion zone rates). At the end of the month you get billed for that month's charges. You can also have multiple personas if you have a work vehicle/card.
In parts of south Florida there's a somewhat similar system where there's only one app you can use and money is taken immediately for the duration of the time you choose (with a small service fee included, of course). If you move your car before the expiration of your purchased time, you lose that value unless you repark in the same area [1]. The similarity is that the app will remind you that your parking is going to expire soon and you can simply extend (and pay that small service fee again, of course). I've seen this prepay-via-app model at various private parking facilities in other US cities as well.
[1]: The system uses number codes for what area you're parked in so you don't need to have location services necessarily (e.g. parking garage) with the code changing every couple streets.