TennisACE turns your Apple Watch and iPhone into a personal tennis coach. Unlike general fitness apps that log tennis as a generic workout, TennisACE is built specifically for the sport. It captures real-time health data — HRV, METs, and Activity Rings — while simultaneously using AI to analyze your stroke mechanics. Point your iPhone at your game and get instant feedback on forehand, backhand, and serve technique. The app surfaces tennis-specific stats that go well beyond calorie counts, helping players identify weaknesses in their swing and track improvement over time. Health data syncs seamlessly with Apple Health, so your rings close and your training history stays in one place. Built for recreational players who want coaching-level insight without a coach on the court.