Do you build your own apps for it? I'm interesting in understanding how hackable it is? For example, can you write an app that pulls the GPS data from a run off it, or is that data readily accessible somehow?
Not OP, but you can't really make your own apps for it. There are third party clients for it, though, and you can export data through them.
I like mine, except for the fact that the front fell off and I had to glue it back on. The battery lasts for 3 or 4 weeks, you can receive notifications (but not respond to them) and it looks fairly stylish.
I haven't done any hacking of any of my smartwatches. If that's important to you, then I don't really have any recommendations for you (and it highlights my point about different people's definition of "comparable").
I want my watch to have time/date, alarms, timers/stopwatches, the ability to read phone notifications, always-on screen, and battery life measured on the scale of weeks. Step and heartrate tracking are also nice perks that the Amazfit Bip also includes.