A limit a parent sets is a wall you spend energy climbing. A limit you set is a deal you made with yourself, and the only thing it needs is a way to hold when you are tempted to break it. That is the gap every reminder app falls into. It assumes that being reminded of your intention is enough. At 11pm, after a long day, it is not.
ScreenFine is built for the moment your own intention goes quiet. You pick the daily limit and the apps it covers. When you cross the line, those apps lock at the operating-system level, not behind a popup you can swipe away. The phone, messages, maps, and calls still work. The feeds that eat your night do not, until you earn them back.
You earn the unlock with something real: 25 camera-counted pushups, 25 squats, 1,000 verified steps, or 10 mindful minutes. Going over never costs money. The only thing you ever pay is the flat dollar a week, and your body, not your wallet, settles the overage.