Fitbit Charge 3 vs Charge 4: Which fitness tracker should you buy?
Fitbit Charge 3 receives an update with Charge 4 features - GSMArena.com news
Amazon.com: Fitbit Charge 3 SE Fitness Activity Tracker Graphite/White Silicone, One Size (S and L Bands Included),1 Count (Pack of 1) : Sports & Outdoors