Me.
I use it for the vibrating alarm every morning, checking who is calling me when my phone is in my pocket (or bag or bike jersey) in a silent/noisy environment, checking/reading texts, other notifications (Twitter, G+, don’t use FB notifications), controlling Spotify that’s running on my phone when the phone is in my pocket (combined with bluetooth headphones), counting steps (just out of vague interest), looking like a God from the future, recording heart rate/distance while running (with ANT+ strap).
Oh, and telling the time.
It can also make my phone ring remotely if I’ve mislaid it and it’s in range (overrides having the phone on silent too). Only used this once in anger. Phone was in my back pocket.
Battery lasts 3-4 days to a week.
Biggest gripe I have is that they seem to have lowered the threshold to illuminate the display – it’s a “double tap” but it senses the vibration/movement and hence tends to stay lit up most of the time I’m riding due to the vibrations.
I’ve been wearing it since mid-December. It’s a good compromise between a basic fitness band and a smartwatch.