Amazon calculates a product’s star ratings using a machine learned model instead of a raw data average. The machine learned model takes into account factors including: the age of a review, helpfulness votes by customers and whether the reviews are from verified purchases.
I had this for a week and really tried to love it. Ultimately it is just *riddled* with bugs. I should have read more online reviews of problems before I bought. 1) GPS tracking doesn't work or only partially works when tracking fitness. Sometimes it would simply record nothing, often it would starting at exactly the 1km mark. Incredibly frustrating. 2) Sleep tracking completely misses deep sleep. 3) Spotify is so buggy it actually does not work full stop. 4) All other apps are incredibly unstable, including Samsung apps. 5) Using any features drains the battery life ridiculously fast. Just playing with Spotify for about 90 seconds after it crashes repeatedly on a run causes the battery to drain about 7%.