Activity trackers are popular these days, and there's no bigger brand in the space than Fitbit. While activity trackers are mainly used by adults, a growing number of them are designed just for kids, along with models that are suitable for older kids to wear. The newest model for young ones is the Fitbit Ace 3 , which offers some simple yet meaningful updates over the previous-generation Ace 2, making it the best kids Fitbit you can get. But depending on how it will be used, there are other Fitbits worth considering, too. Best overall: Fitbit Ace 3 Fitbit's latest device, this one, is designed specifically for kids aged 6 and older. As an update to the previous-generation Ace 2, the main upgrades include longer battery life at up to eight days versus five, more animated clock face characters that change and grow as the child works toward reaching their daily goals, new modes like do not disturb, sleep (which halts notifications and dims the screen), and water lock, which de