Fitbit OS 5.1 update: All the new features coming to the Sense and Versa 3

The latest software update brings Google Assistant support to Fitbit's newest smartwatches along with text dictation and the ability to answer calls.

Lexy Savvides Principal Video Producer
Lexy is an on-air presenter and award-winning producer who covers consumer tech, including the latest smartphones, wearables and emerging trends like assistive robotics. She's won two Gold Telly Awards for her video series Beta Test. Prior to her career at CNET, she was a magazine editor, radio announcer and DJ. Lexy is based in San Francisco.
Expertise Wearables | Smartwatches | Mobile phones | Photography | Health tech | Assistive robotics Credentials
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Lexy Savvides
2 min read
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If you've got a Fitbit Sense or Versa 3, you have a few new features to explore on your smartwatch. With the update to Fitbit OS 5.1, you'll now have the option to use  Google Assistant  as your Fitbit's voice assistant instead of Amazon's Alexa, which has been available on the watches since launch. The update will also allow you to take calls on the watch when your phone is nearby, dictate text replies from your wrist (Android only) and access more health data while you sleep. 

Read more: Fitbit Sense, Versa 3 and Inspire 2 are here: How to decide which to buy

The update to OS 5.1 came just a month after its last software update, which activated the built-in electrocardiogram (ECG or EKG) on the  Fitbit Sense  in the US, some European countries and Hong Kong. 

Fitbit launched two new smartwatches in 2020: The high-end Sense with advanced health tracking features including ECG, stress detection and temperature tracking; and the  Versa 3 , a continuation of the line with design upgrades and built-in GPS. 

Here's everything else that's included in the update:

  • Blood oxygen readings will automatically be tracked as you sleep. Previously this data was only available the next morning if you selected a specific SpO2 watch face the night before. If you prefer to see the readings on your wrist, there will be seven new SpO2 faces to choose from in the App Gallery by the end of the year.
  • Choose between  Alexa and the Google Assistant on your wrist. Switch by going to the Fitbit app and finding the Voice Assistant option within your smartwatch model in the account tab. If you choose the Google Assistant, you'll need to log in to your Google account. 
  • Alexa will now speak responses back to you. Previously, Alexa would just display responses on the screen.

The update started rolling out in the US last month. Unfortunately, older Fitbit models such as the Versa 2 and Ionic won't receive the OS 5.1 update.

Being able to take quick calls on your wrist and respond to messages with your voice makes the newer Fitbits more competitive with the likes of the Apple Watch Series 6 , Apple Watch SE and Galaxy Watch 3 . We'll be updating our review of the Fitbit Sense once we've had a chance to test out the new features.