Google has upgraded Fitbit's sleep tracking with 15% more accurate algorithms that can now distinguish between actual sleep and time spent awake in bed. The improvements include better detection of 3 AM wake-ups, weekend naps, and transitions between light, deep, and REM sleep stages. This enhancement comes as part of the Gemini AI-powered Fitbit Personal Health Coach.

Next month, U.S. Fitbit users in the Public Preview can link their complete medical history to the app through partnerships with b. well and CLEAR. This includes lab results, medication lists, and visit history, allowing the Coach to provide personalized health recommendations based on actual health data rather than just step counts.

The integration raises privacy concerns as Google leverages its advertising business model while handling sensitive health information. Despite Fitbit's assurances that records won't be used for ads and users retain control over their data, the service requires a Premium subscription. While the Coach can summarize lab results, it cannot provide medical diagnosis.