Inside the Charge 3 are an accelerometer, gyroscope, optical heart rate monitor, and an SpO2 sensor for tracking blood oxygen levels. The Charge 3 is the third Fitbit device to include an SpO2 sensor, following in the footsteps of both the Fitbit Ionic and the Versa smartwatches. However, currently the SpO2 monitor lies dormant inside all of these devices as Fitbit hasn't made use of it yet.
Smartwatches are still a very new thing to a lot of people, and for good reason. You don’t absolutely need one to get through the day, and some of the best smartwatches are much too expensive for many folks out there. With that said, they are good for a lot of things. They can provide you with an easy way to get information, allow you to dismiss or reply to new messages without having to pull out your phone, and much more.
What’s on display?: Most smartwatches have full-colour displays, though the underlying technology will determine how good the screen looks. There has been a move towards AMOLED (active matrix organic light emitting diode) displays, as used in the Apple Watch which present a bright screen, crisp text and accurate colours. Fitness trackers tend to have lower-quality screens and may not present in full-colour, partly to save battery life.
Samsung's Galaxy Watch, a Tizen OS watch (starting at $329), is our favorite smartwatch for Android users. In addition to up to four days of battery life and a great design, the Galaxy Watch offers built-in GPS, heart rate sensor, water-resistance, Samsung Pay support, plus a nifty rotating bezel for navigating the interface. You can also download music from Spotify to the watch for offline listening. However, you get far fewer apps than you would with a Wear OS watch.