Tell me about your Activity Tracker

Showmm

I know it's been asked before, but the more answers, the better.

1. Which device do you use?
2. Do you use it all day or only when doing fitness activities?
3. What do you like/love about your device?
4. What isn't so great about your device?

I look forward to all your replies - they are going to help me decide which one to get for myself. It's my reward for having logged all of January faithfully.