Best answer by Gordo26
I've had a few smart watches in my time from Sony to Huawei. For me my current Huawei Watch 2 is brilliant for my lifestyle.
It runs off the Android Wear operating system
Battery life is 2 days continuous use and then it drops into an energy saving mode which can make it last another day tracking steps and displaying time. Charging time is quick 0 to full in around 1hr so no big deal if it's running low.
Its currently on Amazon for £139.99
Is waterproof and available in 2 styles - Classic or Sports
I can track my runs/cycles, I can pay for items with Android pay and can check my heart rate at anytime.
The can also change the faces on my watch if perhaps im going to a wedding and would like a stylish watch face, then if im going a run just change to a simple digital face for quick glances.
The straps are changeable as well however I have stuck with the original sports band.
If you want a watch with longer battery have a look at the Huawei GT, I haven't owned that because I wanted to stay android wear is so I can't give any other personal views on that.
Hope this helps a bit x