Fitbit's Charge 4 can wake you up when you feel well-rested

It's also smarter about using your phone's GPS.

Valentina Palladino/Engadget

You now have more reasons to wear your Fitbit Charge 4 around the clock. The 9to5Google team reports (via The Verge) that a Charge 4 update has introduced two major features to improve your sleep habits and encourage more exercise. Smart Wake sets alarms based on when you’re likely to feel rested, rather than a set time. So long as you have that leeway, it could help you start your days on the right footing.

The other tentpole addition, Dynamic GPS, switches to your phone’s positioning when nearby to improve battery life. You won’t have to worry about your activity tracker running out of power just because you tracked your latest bike ride. Given that the Charge 4 can’t use its own GPS for more than five hours on a charge, this could get you through more workouts before plugging in.

The update is available now to Charge 4 owners. Neither will necessarily sell you on Fitbit’s hardware by themselves, but they could make a better case for a tracker over a smartwatch that will likely need more frequent charging.