The physics of a better game.
Film one stroke. TopSpin reads your body the way a coach would, flies your ball the way an engineer would, and hands you the one thing worth fixing.
ON-DEVICE. Your footage never leaves your phone. No sign-up to try it.
A struck ball is a chaotic system, so we treat it like one.
Once it leaves your strings the ball feels three things: gravity, drag from the air, and the Magnus force from spin. There's no clean formula for where that lands, so we don't fake one with a smooth arc. We march the flight forward step by step, then fly it a few hundred times with tiny variations to get honest odds.
Aim the reticle and watch the spread grow as you get greedy with depth and the lines. That spread is the margin you're actually playing with.
The court learns to see you.
Drop in a clip and a pose model traces 33 landmarks through your swing, frame by frame, right on your device. At contact we measure your elbow, knee and trunk angles against stroke-specific targets, then score the whole motion out of 100. You won't get generic tips. The feedback is about the swing you actually made.
Your session assembles itself.
Every flaw the analysis turns up is wired to drills that fix it. Your worst habit gets worked first, the session fits the minutes you actually have, and every line tells you why it's there. Saved workouts sit on your Stats page next to your form trend, so the loop closes on its own.
Your footage stays on your phone. Full stop.
Pose runs in your browser · No account required · Analytics self-hosted, cookie-free
Curious what your forehand is hiding?
One clip. A few seconds. One clear thing to fix.