I didn't buy an Apple Watch because of a) the cost and b) not wanting to charge a watch every day. My Amazfit Bip is 2.5 years old, and has
* Heart rate detection up to every minute (automatically speeds up to real time during workout)
* Bluetooth Smart sensor functionality, so I can use it to report heart rate to compliant apps like iSmoothRun
* Sleep tracking
* 25 days of battery life (real world, not specification)
* GPS (although I never use it, preferring GPS on my phone through iSmoothRun)
* Notifications display
* More than 20,000 user-contributed watch faces
* $60 price when I bought it; the successor Bip S is about the same price today
It doesn't have Apple Watch's arrythmia or blood oxygen detection, and there is a UI bug that the company never fixed after it appeared last year, but otherwise Bip has done exactly what it promised and more.