It also packs Fitbit’s new SpO2 sensor, which was recently ... find trackers annoying to wear to bed, the Charge 3 isn’t exactly tiny. But it is light and comfortable, I’ll say that much.

The Charge 3's also Fitbit's first fitness tracker with an SpO2 sensor (same one as on the Fitbit ... sleep composition (i.e. light, deep, REM), and revitalization (heart rate levels and breathing ...

Fitbit is also launching the beta version of its Sleep Score program. Using the SpO2 sensor and 24/7 PurePlus heart rate tracking, the Charge 3 will help users understand their sleep patterns better.

The data garnered from this addition informs more intuitive sleep tracking and breathing monitoring in the Fitbit app. The Charge 3 lacked full use of the sensor at launch. It did eventually ...

The Inspire 3 borrows its design traits from Fitbit ... the Charge 5 it replaced. The device also tracks SpO2 levels while you sleep and sleep data, boasts an ECG and EDA stress sensor, and ...

three light sensors, on the back. Just like the Charge 5. However, Fitbit does claim it is the most accurate heart rate sensor it has made yet, so perhaps there are more substantial improvements ...

The reflective screen can be tough to see in the morning light ... heart rate and time. Like Fitbit’s Versa and Ionic smartwatches, the Charge 3 has an SpO2 sensor for measuring blood ...

So you want to buy a Fitbit, but you can’t decide between the super-affordable, super-cute Fitbit Inspire 3 or the slightly more expensive Fitbit Charge ... of your deep, light, and REM sleep ...