Sleep tracking does not work. But they accepted the return

3 stars for looking sturdy and being a good price.Loss of stars because the measurement system is faulty. You measure the circumference of your finger but the listing measurement is diameter. This is the second one sent back. Having worked out the diameter of my index finger I find my size is listed on the main pictures but not an option in the size choice.I wish listing was not only accurate in choice but also measurement. Why measure the circumference and not offer it as a sizing choice.Such a shame, it looks really good, strong yet thin enough to forget it's on. Loads of important health spec too for those of us with chronic illness.

This is the 2nd Smart Ring I've purchased within 1 week period and this one is worse than the first was. This appears as an O Ring brand and the app that it takes is called Luck Ring. It does not require a subscription service to use the app and ring so that is a good thing. The ring was well packaged and received on time. I really like the charging case that comes with it as it lets you charge it on the go - no plugging in to recharge your ring just drop it in the case and it recharges. The app was easy to setup and the binding process was quick and simple - no issues connecting with the ring. This ring is marketed as being able to measure your heart rate, blood oxygen, blood pressure, sleep, workouts and a couple of other things as well. Well, it does not track or measure blood pressure but instead monitors HVA. After charging my ring to 100% and connecting to the app, it tracked my heart rate pretty accurately but it stated my blood oxygen rate is always 98 - 99% which is not accurate. I also had a 30 min workout last night and it didn't pick that up while I had the ring on. It didn't read my sleep last night either which is really poor for a smartring to not do. I even reset the ring and reset the app - when I reset the app for android, it showed everything in Chinese which really irritated me. I had to reset the app again and then it displayed everything in English. The ring fit perfect on my right ring finger and wasn't too thick or too wide and is comfortable to wear all day and all night, it looked nice and the battery seemed to last a long time for the period of time I used it. I am returning this ring and will purchase a different brand. I'm very displeased that the seller advertises that it monitors your blood pressure but it doesn't. and it did not track my workout or my sleep is a huge fail in my book.

Nice Starter Health tracker ring. Light, comfortable, basic health info. More for someone who likes games and pretty graphics. Not super reliable on the health data. Compared to the $200 level rings, there were some differences in heart rate and steps. A few times the Stress Level score went way high, when the more expensive ring (RingConn brand) showed no stress at all. I wore both for 2 days to compare.If purchasing, wear a RING PROTECTOR over it as it scratches up really bad.

Charged to 100% and died before end of day. Less than 10 hours. Large difference in results from Fitbit. Easy to return.