Fitbit has unveiled the third device in the Fitbit Charge family, the Fitbit Charge 3, and the new version adds SpO2 tracking among other health tracking improvements. The device will be available starting in October.

“With Charge 3, we are building on the success of our best-selling Charge franchise and delivering our most innovative tracker, offering an extremely slim, comfortable, and premium design, along with the advanced health and fitness features our users want. Charge 3 gives existing users a compelling reason to upgrade, while also allowing us to reach new users who want a sleeker, more affordable wearable in a tracker form factor,” CEO Fitbit James Park said in a statement. “Our commitment to consumer choice and ability to meet the demand of millions of users by offering a range of products, from trackers to smartwatches, will enable us to expand our share of the overall wearables market.”

The relative SpO2 sensor will allow the device to estimate changes in blood oxygenation levels and track breathing disruptions which could be indicators of allergies, asthma, or sleep apnea. As Fitbit noted in its release, the company is continuing to work with the FDA as part of its Pre-Cert pilot, with the goal of developing FDA-regulated software for conditions including sleep apnea and atrial fibrillation.

On the topic of sleep, the company also announced a new beta for its Sleep Score that will bring an improved picture of sleep quality tracking, using heart rate sensors, to users.

"Fitbit continues to harness its data to give users actionable insights into their health and wellness. For example, we've found that one in four people get significantly more sleep on weekends than weekdays, which implies they are trying to make up for reduced sleep during the week,” Shelten Yuen, VP of research at Fitbit, said in a statement. “We can deliver insights to these users through the Fitbit app to make them aware of how this behavior affects their wellbeing and suggest how to set up a sleep schedule. In the future, we hope to provide more guidance to our users to reduce the risk of disease so they can become the healthiest versions of themselves.”

Charge 3 is also water resistant to 50 meters, includes GPS and run detection features, features improved accuracy in heart rate tracking, and allows users to tap into Fitbit’s social-driven community features. Coming soon is an on-device dashboard that will allow users to view metrics like hydration, sleep, weight, and female health tracking right on the Charge 3’s screen.

The smartwatch will also follow in its predecessor’s footsteps with non-health features like Fitbit Pay; call, calendar, and text message notifications; and a number of available apps. The device will retail for $149.95 in the US.