Today, Fitbit announced the availability of three new fitness trackers: the Inspire 3, Versa 4, and Sense 2. All successors to previous-generation devices, the three run the gamut from Fitbit’s highest-equipped to most basic fitness wearables.

“Basic” is a relative term among fitness trackers, as they all continuously edge closer to full-blown smartwatch functionality. The Inspire 3, in particular, adds blood oxygen monitoring during sleep and a full-color AMOLED touchscreen to the entry-level tracker, which already can receive phone alerts, like texts, calls, and app notifications. Setting the display to the optional “always on” setting takes battery life estimates down from 10 days to only three, which is much more in line with full-featured smartwatches, though less than Fitbit’s Sense and Versa watches.

By contrast, the Sense 2 and Versa 4 are the two most-capable trackers Fitbit offers. They’re both rated for about six days of use (without the always-on-display enabled) and now feature fast-charging capability that Fitbit claims can give you a day of battery life from only 12 minutes of charging.

The Sense 2 stands atop the Fitbit family, packing ECG sensors for Atrial Fibrillation (AFib) detection, EDA (electrodermal activity) for stress measurement, GPS, blood oxygen, and heart rate tracking. The previous Fitbit Sense had all these, too. But the Sense 2 builds on this by incorporating new hardware and software for continuous (and therefore more useful) AFib and stress monitoring.

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Fitbit calls the new hardware a “Body Response” sensor, which will monitor your stress levels throughout the day and alert you when you’re under stress. If it senses stress, you’ll get recommendations for guided breathing or meditation exercises that you can do either on-wrist or in the Fitbit app. The Sense 2 can actually take on-demand EDA readings through the display itself "using a technique that turns metal into vapor, allowing [them] to integrate the metal electrodes of these sensors directly into the display glass of the device," according to Fitbit. Sounds high-tech, but ultimately it just means a slightly smaller bezel without the ring around it for EDA readings.

The new algorithm for continuous AFib monitoring has, in some form, been in the works since 2020, when Fitbit launched a heart study centered on detecting AFib. Before making its way to the new Sense 2, the company proved that its algorithm could detect 98 percent of AFib cases in a sample size of more than 450,000 people.

Passive AFib detection is available on the Sense 2, Sense, Versa 4, Versa 3, Versa 2, Inspire 3, Inspire 2, Charge 5, Charge 4, and Luxe trackers. But it only works while the user is sleeping. It uses photoplethysmography (PPG) to detect changes in blood volume (and therefore heart rhythm) that might indicate signs of atrial fibrillation (AFib). That’s in addition to the Sense’s still-included spot-check AFib sensor that existed in the previous Sense generation. Spot checks require users to sit still with their palm covering the display, whereas passive monitoring does not. Both the sensor and PPG algorithm have been cleared by the US Food and Drug Administration and CE marked, meaning they’ve met both the US's and EU’s requirements for safety, health, and environmental protection.

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The Versa 4 doesn’t add any new hardware over the Versa 3, meaning no Body Response sensor here. Instead, it received a minor physical update, becoming slightly thinner and lighter while bringing back the physical button for more reliable use.

As for the UI, both the Sense 2 and Versa 4 have been tweaked to offer customizable data tiles, compared to the static presets of old. Fitbit says Google Wallet and Google Maps will also come to these devices “in the coming months.”

In the meantime, users can enjoy twice as many activity modes (40-plus) on their new devices. This introduces modes for high-intensity interval training, weightlifting, CrossFit, skiing/snowboarding, and dance, among others. Fitbit says it has no plans to bring these new activity modes to previous-generation Fitbits, but it will "continue to evaluate the opportunity."

One thing remains certain for all these new devices, though: Many of Fitbit’s most useful tools and insights (beyond raw data collection) are locked behind the company’s Premium subscription. That includes Daily Readiness scores for assessing your physical recovery and recommending suitable workout options for each day, Sleep Profiles to help users understand their sleep patterns and how they can change over time, and Wellness Reports and Health Metrics, which provide longer-term (30 days to a year) graphs, trends, and averages for a range of biological data including heart rate variability, skin temperature, blood oxygen levels, sleep patterns, weight fluctuations, and activity levels.

The growing trend of paywalled data in the fitness/wellness tracker world is the bane of my existence. It only reinforces that access to wellness and health can be measured by one metric: wealth. Fitbit offers six free months of Fitbit Premium for new users who purchase a Sense 2, Versa 4, or Inspire 3. Unfortunately for the Inspire, that’s six months less than Fitbit used to offer.

All three devices are available for preorder starting today. The Sense 2 retails for $300 ($50 more than its predecessor), the Versa 4 for $230 ($30 more than the Versa 3’s launch price), and the Inspire 3 for $100 (matching the Inspire 2’s original price).

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Listing image by Fitbit