Question: what is the difference between charge 2 and 3?
Answer: Both the Fitbit Charge 2 and Fitbit Charge 3 have a rectangular screen and a band that's as wide as the body, but the design has been refined and tweaked for the Fitbit Charge 3. ... The screen is a much bigger difference though, as the display on the Fitbit Charge 3 is 40% larger than the one on the Charge 2.