I've only had the watch for a couple of weeks. I've not used the activity and cardio fitness features yet and I can't comment on those. The basic features of being an extension of my cell phone work great in terms of making and answering calls as well as Google. It was relatively easy to set up. I say "relatively" because this watch could use as good manual and there isn't one. While setting it up, a feature locked and I wanted to shut the watch off and start it up again but it took me forever to find it in an obscure place in the phone app (you push the middle button in for more than 3 sec). The biggest issue was overheating during charging. The watch would get so hot I couldn't hold it. Actually, this is my 2nd watch. I sent the 1st back for this reason. When the 2nd watch exhibited the same problem, I did a Google search and found that the solution was to charge it in airplane mode. How to get it into airplane mode? It took me a while to figure it out. Again, no manual. No manual and overheating are why I gave the watch 3 stars instead of 5. Fossil really need to correct the overheating problem.