SwimCoach: Stroke Analysis

SwimCoach films a freestyle swim and scores its biomechanics — entirely on your iPhone. Record from the pool deck or import a clip you already have. A neural network reads pose keypoints from every frame, scores three-second windows, and turns them into a 0–100 technique score with a letter grade. You see which faults showed up, exactly when they happened, and which drills address them. WHAT YOU GET • A technique score for every swim, with the trend across sessions • Detected faults — body sag, elbow collapse, knee overbend, kick rate, stroke asymmetry • A skeleton overlay on your own video, so you can see what the model saw • An issue timeline: tap a mark to jump to the moment a fault peaked • Drills matched to the faults you actually have, not a generic list • Stroke count, stroke rate, kick rate and left/right asymmetry • Export the overlaid video, or a report card for sharing TRY IT WITHOUT A POOL Three real swims ship inside the app — freestyle filmed from the deck and from underwater. Running one puts it through the identical analysis your own footage gets. The score and the faults are what the model genuinely found on those frames. Sample swims stay out of your history, so they cannot move your trends or your streak. FILMING THAT WORKS An on-screen framing guide and a live level indicator help you get a usable shot: side on, camera at the waterline, whole body in frame. PRIVATE BY CONSTRUCTION There is no account and no sign-in. The app makes no network requests at all. Your videos, the pose data, and every result stay on your iPhone. No analytics, no tracking, no third-party SDKs. SwimCoach analyses freestyle technique. It is a training aid, not a medical or diagnostic tool.