Headroom: Caffeine Tolerance

Caffeine works best when you don't need it every day. Headroom estimates where you are, so you can save it for the days that count: an exam, a long drive, a big workout. HOW HARD IT'LL HIT TODAY Every caffeine day builds tolerance; days off let it fade. Headroom tracks that load and estimates how much of caffeine's usual effect you're likely to feel today. Preview a dose before you take it: slide the amount, time, and bedtime, and see the curve on top of what's already in your system, when it peaks, and how much is likely left when you go to sleep. ROOM BEFORE WITHDRAWAL See how many more milligrams today would likely keep you under the withdrawal line, the point where a day without caffeine tends to bring headaches or fog. If you're already past it, Headroom can lay out an optional step-down plan instead of a cold stop. LOG IN SECONDS One tap from the app, a home screen widget, or…