Buy Fitbit One -

The Fitbit One still works with the current Fitbit app , but you may need the original USB charging cable and potentially a Bluetooth-enabled smartphone to set it up. Modern Alternatives

Since these devices are several years old, the internal lithium-polymer battery may have degraded. If buying used, ask the seller how long a single charge lasts. buy fitbit one

If you want the "clip-on" style without the risks of buying a discontinued device, consider the . While it is designed as a wristband, Fitbit sells an official Clip Accessory that allows you to wear it on your belt or pocket just like the original One. The Fitbit One still works with the current