I have mixed feelings when it comes to this watch. Overall it does a decent job of keeping track of your heart rate, blood oxygen level and the steps you have walked throughout the day and the watch looks rather nice. However I feel that the user interface is rather clunky and at times it appears to lag sometimes taking 10 seconds before it does what you ask it to. Also I find that it misses a few of the exercise options that I participate in. This is somewhat remedied by the fact that you can pair the watch to work with Google Fitness which does an excellent job of tracking your exercise and it has many of the options that I participate in.
I am happy with the battery life, not so much with the app and face options, etc.
I like the watch but the app running all the time is very annoying. This is the only app I've had that doesn't allow itself to be shutoff or only run while being used. Pairing was also difficult.
The watch is nice looking. Other then that it's not worth it. You can see time in dark. Notifications are unreadable, you can't response to any notifications. Menu is complicated. 18 day battery is good. But watch itself with the features that are unusable not worth it. Won't recommend if you are buying for features. If just want to check time now and then, step count etc then may be OK.