See exactly why
your serve isn't improving
Your serve happens too fast to feel. ServeMaster freezes the key moments—toss release, knee load, weight transfer, follow-through—and shows you exactly what your body did. Not what you thought it did.
Built by a tennis lover
Kinetic chain breakdown into stats and visuals
We break down the kinetic chain into measurable stats. Each one shows you exactly where you're losing consistency—with numbers, not guesswork.
Toss Arm Angle
Your arm angle at the moment of release—measured automatically. Target: 165°-180°. A bent arm sends the ball forward instead of up. Most players don't realize they're doing it until they see the number.
Knee Bend
How deep you load before pushing up. Target: 105°-125°. This is where leg drive comes from. The app catches the exact frame at your lowest point and measures the angle.
Vertical Rise
How much your body actually lifts from load to contact. Target: 15+ cm. Tracks your center of mass frame-by-frame. You'll see exactly how much (or little) you're pushing off the ground.
Follow-Through
Did your arm cross your body's midline? A complete follow-through means you accelerated through the ball, not at it. Simple yes/no check—no guessing.
Frequently Asked Questions
Ready to Ace It?
Join the wave of players using AI to refine their mechanics. Download ServeMaster today and start your transformation.
Compatible with iOS 16+. No sensors required.