I purchased my Fitbit alta HR in November of 2017. I am pleased with how it works although it is a little glitchy as one of the reviewers said. For example, it does not always activate when I turn my wrist towards my chest. I have to tap it several times to get the screen to come on. But even that didn't bother me to much. However, I was disappointed when the wristband began detaching from the Fitbit and I called Fitbit only to find out that Groupon is not an authorized dealer so I am not covered by the warranty. Apparently, I have no warranty with Groupon either, so tough nookies for me. I'll be more careful in future purchases from Groupon. I don't usually have problems with them but this certainly is upsetting. This is a lot money to spend on a product that has no warranty. Buyer Beware!