Somnus: AI Sleep Tracker: Find what ACTUALLY drives your sleep quality

Hey PH! I'm Seb, a solo iOS developer from London. My first app Thryve Wellness was featured in Apple's Apps We Love, and Somnus is what I built next. The idea came from a simple frustration: every sleep app shows you what happened, but none tell you what to actually change. I sleep 7 hours, great. But why was Tuesday so much better than Thursday? Somnus looks across 25+ signals from Apple Health - steps, HRV, heart rate, exercise, bedtime consistency, sleep stages - and finds the specific patterns that move your sleep quality. Not generic tips, your actual data. The bit I'm happiest with is the experiment system. Find a pattern, set up a structured test, and prove whether changing a habit actually works with before-and-after tracking. All the AI (weekly reviews, narrative summaries, daily reflections) runs entirely on-device using Apple's FoundationModels. No server, no accounts, nothing leaves your phone. Free tier includes sleep scoring and trends. Pro unlocks the full insight library and experiment system. Would love to hear what you think - especially from anyone who tracks their sleep and feels like they've got the data but short on answers. Link: https://apps.apple.com/app/somnu...