Fitbit has updated its Fitbit OS operating system for its health smartwatches.

Fitbit OS 4.1 is compatible with the company’s smartwatches, including the Versa 2 and Ionic, plus the original Versa and Versa Lite.

It begins rolling out to Fitbit smartwatch users from the first week of December.

The Versa 2, Fitbit’s latest smartwatch release, gets a new enriched always-on display mode (with five additional clock face options), expanded capabilities for its built-in Amazon Alexa voice assistant, and a new advanced heart rate algorithm that the company is hailing as “the best tracking yet he latest smartwatch tracker” - read our Fitbit Versa 2 review.

The new PurePulse heart-rate tracking algorithm uses machine learning to recognise the unique signature of heart rate in the optical sensor, leading to higher accuracy overall.

Now in colour, the Always On displays feature full health and fitness stats, with faster transitions between always-on and active views on the AMOLED display, but reducing battery life from six days to just two – although that is still longer than the battery life of the Apple Watch even when not Always On. Find out more about Fitbit vs Apple Watch.

OS 4.1 delivers Smart Wake, a silent on-device alarm that uses machine learning to wake you during an optimal time of your sleep cycle while in light or REM sleep within a 30-minute interval prior to the start of your set alarm.

Fitbit Versa 2 smartwatches

A new Agenda app will “help you take on the day to live your best life and help manage your daily schedule on-the-go”.

A new clock face switcher lets you store up to five of your favourite clock faces from nearly 4,000 available in the Fitbit App Gallery directly on-device so you can quickly and easily swap clock faces. If you fancy counting, there are 3,275 clock faces available for the Ionic, 3,960 for the Versa2, 4,484 for the original Versa, and 3,615 for the Versa Lite.

Talking of the Fitbit App Gallery, this gets a new five-star rating system - allowing users to rate and recommend their favourite apps and clock faces with the Fitbit user community.

Versa 2 owners can now use Amazon Alexa to start any of the now 20 exercises from their wrist. For example, you can ask Alexa to start a run with Fitbit and automatically start tracking against your personal fitness goals and daily activities.

Another feature promises to save energy and avoid losing step counting by notifying users when their battery is running low, and automatically disables select features to get you back home before the battery conks out. This is activated when battery reaches 8% remaining. These include some of our favourite tips on saving Fitbit battery life.

Find out which Fitbit is best for you.

New Premium features

Fitbit is also rolling out new content and tools for its Fitbit Premium membership (subscriptions start at £7.99/month), including a personal wellness report, developed in consultation with leading medical professionals from institutions such as the University of California. There will also be new programmes, challenges and wellness content released, plus workouts from popular brands like Daily Burn, Down Dog, Gaiam, PopSugar and Whil.

Fitbit Wellness Report  

The new personalised Wellness Report - developed in consultation with clinicians and medical professionals - gives users an in-depth analysis of their Fitbit activity, sleep, heart rate and weight trend data for the previous 30 days or past year for long-time users. 

This can be shared with a general practitioner, personal trainer or nutritionist to review your health trends over time, to better identify a potential health issue or help manage ongoing conditions.

Fitbit Premium workouts

New workouts include yoga sessions from Down Dog and Yoga Studio by Gaiam - focused on strength, flexibility, balance and restoration.

Premium members also gain access to a new Mindfulness section in the Discover tab of the Fitbit app, with a variety of mindfulness and meditation sessions and mini-courses from Whil, as well as breathing exercises and soothing audio tracks designed to help you wind down and get ready for bed.

Fitbit promises that new adaptive, collaborative and customisable challenges and games are coming to Premium in the next few months. These include an All for One challenge to work with your family and friends toward a shared goal, a Custom Challenge where you choose a specific activity and duration to compete against and an interactive game of Get Fit Bingo where the first to complete a row or pattern of activities wins.