This one failed to connect to my phone's bluetooth or my wife's phone. I contacted the company and it took more than a week for them to respond and they blamed me for not following the instructions and attached the manual that was included in the box.

All other features worked as expected and the consistent HR monitor seemed to function well.

I returned this one and purchased a second one that immediately connected to my phones bluetooth confirming the first one had an issue.

The second one's HR monitor failed within a few days showing no readings. Also after that point it would fail in less than half a day. I pulled it off the charger at 6am and it dies before I finish my lunch.

On a separate technical review the number of notifications it can show is very limited to only a handful of popular American applications. The last time I used it it did not support Hangouts. You can pass data to Google Fit.