Your Apple Watch already knows you skipped that last set. I'm building an app that tells you - want to tear it apart before i write a single line of code? i will not promote

I'm a CS student. I want to build a fitness app. Before I touch Xcode, I want to know if this is actually solving something real or if I'm just building for myself. Here's the core idea: Your Apple watch tracks your reps passively using motion sensors - no camera, now manual logging mid-set. It auto-checks your workout plan as you go. After the session, AI gives you a breakdown: what your plan said, what you actually did, and calls out anything you skipped or cut short. If your plan says 4x10 squats and you