Watches

I have the Apple Watch series 2 and love it as it works perfectly with my iPhone 7 Plus. Tracks all of my daily activity including my swim sessions. While it can track my sleep, I don't use it at night because I found that I actually had a tough time sleeping knowing that my sleep was recorded. Battery life with my new series 2 Apple Watch is about 2 days on a charge which is much better than the original one I had.

i have a fitbit HR, I love it, tracks steps, HR, calories burned, stairs climbed, workouts, and active minutes, and sleep

I have a Fitbit Charge 2 and it's probably my favorite Fitbit (I've tried most of them).
I found some of the other models to be a bit bulky for me (if you are used to wearing a regular watch though this probably won't be a problem for you.)
I also really enjoy the Fitbit community. Lots of friends/coworkers/etc also have fitbits and we enjoy doing challenges in the app.