The app is okay. I had a weird bug for a bit where putting my height and weight in would *refuse* to save, so I was 18ft tall and 29lbs for a few days lol. Honestly if I'm granting access to my Apple Health data anyway, why do I need to put that in again?
The Heart Rate seems fairly close to my Apple Watch, within a few BPM when I've spot-checked it. The Sleep Tracking, which is the main reason I got this ring, seems... somewhat accurate? Sort of hard to gauge. It has a graph and breaks down sleep into three phases: Restful, Light, and REM. It also spits out a Sleep Quality Score but it never seems to dip below the 80s, whether I get over 8 hrs or less than 6.
There's some historical data available in terms of Day/Week/Month, but it's cumbersome to navigate and somewhat inscrutable to analyze. Some charts are interactive and others are static. Some have "Learn More" education and some barely explain themselves. I was previously using the calendar icon in the top right to swap days, but while writing this review discovered I can swipe left-right on the display to access other days.
Overall, the most interesting stat I've learned from wearing this for three weeks so far is that my sleeping heart rate patterns reflect poor sleep. I always seem to have my lowest HR just before waking up, and the educational component informed me that the nadir should be closer to the middle of the night. Yeah, I knew I woke up groggy, but this gives me a new metric to watch.
I'd like to see more data parsing options and some better analytics. Importing and exporting data to CSV would be awesome.