Optic

See every serve.

Prop your iPhone by the fence and hit five serves. Optic finds each one, scores every phase of the motion, and gives you one thing to fix next, with a drill for it.

Coming soon to the App Store For iPhone with iOS 26 or later

How it works

No sensors and nothing to wear. Your phone, a basket of balls, and a few minutes on court.

Top view of a court: the player serves from behind the baseline and the phone stands off to the side, level with the player, facing them. You Phone ↑ To the net
Seen from above: the phone stands level with you, off to the side, so you face it in your stance. Left-handed? Put it on your other side.

  1. Put your phone side-on

    Lean it on the fence or use a tripod. Get your shoes and head in the frame, with room above for the toss. A checklist turns green when the framing, light and steadiness are right.

  2. Hit five serves

    Serve as you normally would. Optic finds each serve by itself and leaves out caught tosses and practice swings, so you never walk back to the phone between serves.

  3. Fix one thing

    Each serve gets a score and one cue for the phase that needs it most. Turn on spoken results to hear it from the baseline, and tap any serve to replay it in slow motion with the measurements on the video.

Every phase of your serve

Optic follows the serve from stance to contact and checks each phase against a target range: the built-in ranges, your own best serves, or another player you've filmed.

Setup
How wide your feet are.
Toss
How high it goes, where it peaks against your front foot, and a straight tossing arm.
Load
Knee bend, hitting elbow, shoulder tilt, and the tossing arm pointing up.
Contact
Contact height, full reach, how far in front you hit, and how far the ball has dropped.
Rhythm
The timing from toss to load to contact, any hitch, and how smooth the swing is.

Serve 3Flat serve

74/100

  • Setup✓ in range
  • Toss✓ in range
  • Load↗ fix next
  • Contact✓ in range
  • Rhythm? not sure

Fix next: load

Bend your front knee more as the ball goes up, then push up into the ball.

An example result. A question mark means the camera couldn't see well enough to call it. Optic tells you that instead of guessing.

Your serves stay on your phone

Optic has no account and no servers. It analyses your video on your iPhone, and a clip only leaves the phone when you share it yourself.

Read the privacy policy