I love my Fitbit and recently got a new one but it’s even smaller than the earlier model, which i lost quite a bit. Here’s a tip i got from Steve Maxwell so you won’t have to worry about losing it again. 
I got a simple chain like you’d use to wear dogtags and made a little necklace out of it. Wearing it around your neck means you never lose it — a big plus cause these are expensive and hard to get in Taiwan. I did wash the earlier one a couple of times and it survived but now I don’t have to worry about it. When doing bench press, I just put it in my pocket. If you’re making fitness a goal this new year, then a Fitbit is HIGHLY recommended!