Pushed to all Charge 4 models via a software update, v1.96.29 brings ‘Dynamic GPS’, an optional new function that can intelligently sense if your phone is with you when you’re using the GPS tracking built into the Charge 4. If it is near, the Fitbit uses the phone’s GPS location to save the tracker’s battery life.

Read our Fitbit Charge 4 review.

If you go for a run without your phone, the Charge 4 will use its own built-in GPS as normal.

One of the great things about the Charge 4 is that it packs full GPS tracking into such a small form factor, but it does mean battery takes a hit. With Dynamic GPS, you should see some battery saved if you tend to run with your phone. It also means you never have to manually switch, which is great.

The other headline new feature is called ‘Smart Wake’, something already available on Fitbit’s Ionic and Versa smartwatches but now on the Charge 4 that lets the tracker set alarms and wake you at the best possible times depending on your sleep cycles. It’s based around the time you set your morning alarm for but will wake you at the best time near then to ensure you’re well-rested.

It’s debatable if there’s much science behind this, but it tries to wake you when you’re in lighter sleep rather than interrupting a deep sleep cycle.

We love the Charge 4 and these two new major features make it an even better buy.

Henry is Tech Advisor’s Phones Editor, ensuring he and the team covers and reviews every smartphone worth knowing about for readers and viewers all over the world. He spends a lot of time moving between different handsets and shouting at WhatsApp to support multiple devices at once.