Battery life was not great

Battery life could be better

The battery life is great and is more comfortable than my previous fitbit.

Battery life was pretty good

Battery life is good enough for me

As it turns out, battery life exceeds the 225 even though I had the heart rate monitoring always off on the 225

Battery life on the 645 is pretty solid, I get 3-4 days between charges and only charge it when I'm showering after a

Pros:- Smaller, looks like a normal watch on my skinny runner's wrist.- Smart watch capabilities.- Heart rate monitoring is actually useful, always on and seems to measure accurately while running.- Add on "widgets".- Stress monitoring is an interesting idea and works well.- Customizable watch faces.- Battery life is far better than I expected

Battery life isn't phenomenal, but it is pretty much as advertised.

The battery life is somewhat limited, but I've gone on four hour runs with GPS and music with no power issues.

Battery life is pretty good too