Spotter: Lifting Form Check

FormSpotter is your pocket spotter: a form check that runs on your iPhone. Prop the phone side-on, pick a squat, a deadlift or an ollie, and go. Every rep or attempt is counted automatically and gets a 0–100 form score and one short cue.

WHAT IT CHECKS
• Squat: depth (did your hips reach knee height), knee track (are your knees caving in), chest angle, and whether your hips rise before your chest.
• Deadlift: back angle through the pull, hips and chest rising together, and a full lockout at the top.
• Ollie (new): how low you crouch, how high your feet pop, whether you pull your knees up in the air, whether your shoulders stay over the board, and how softly you land. Best practised in one spot on grass or carpet.

HOW IT WORKS
FormSpotter uses Apple's Vision framework to estimate your joints in 3D from each camera frame, then measures the angles between them. Because the angles are 3D, a phone that isn't perfectly side-on still reads your knees and hips correctly — something flat 2D tracking struggles with.

PRIVATE BY DESIGN
Frames are analyzed on your iPhone and discarded. No video is recorded, nothing is uploaded, and there is no account.

FormSpotter gives training feedback, not medical advice. Scores are estimates and can be wrong — use them alongside a qualified coach's judgment.