We have seen some interesting smartwatches recently. None of them can be used as a headset though. HeadWatch is different. Not only it pairs with your smartphone to make your life easier, it can be detached to be worn like a headset. The watch is waterproof. It also has a bunch of sensors to monitor temperature, luminosity, and your activities. Its RGB strip lights can be customized for your notifications.
HeadWatch has a battery that should last a couple of days. It is certainly an interesting smartwatch. You can support it on Indiegogo.