The new $329 Fitbit Sense watch includes the ability to measure skin temperature and electrical activity on the skin called electrodermal activity, which can reveal signs of stress, along with heart rate and heart rhythm.

The data also may be able to help diagnose COVID-19 in users even before more obvious symptoms arise, according to some preliminary research. Fitbit has a trial involving 100,000 users, but such studies are still ongoing and no regulator has approved the use of any smartwatch to detect COVID-19.

“The results are incredibly exciting,” Fitbit CEO James Park said during a press briefing on Monday ahead of the announcement. “We see signs of illness from health metrics like breathing rate and heart rate variability one to two days before symptoms are even reported by the user.”

The presentation also included videos of people using Fitbit products while exercising wearing masks and images of people and businesses affected by the pandemic. “We believe that our mission was made for this moment and we quickly innovated and mobilized our entire company to help,” Park said.

The new top-of-the-line Sense has a stainless steel body, built-in GPS, and a speaker and microphone for connecting to Amazon’s Alexa or Google’s Assistant (though it still needs to reach the Internet via a linked phone). While it still lacks some features of Apple’s latest Apple Watch Series 5, like detecting when users fall down or the ability to connect directly to cellular networks without a phone, the Sense lasts for six days on a battery change, three or four-times longer than Apple’s watch, Fitbit says.

Fitbit also unveiled a mid-range watch called the Versa 3 for $229 and a simpler activity tracking wristband called the Inspire 2 for $100. All three wearables are available for pre-order immediately and will ship in late September, Fitbit said.

The company, which is in the process of being bought by Google for $2 billion, could certainly use a hit. Once the pioneer and unquestioned leader of the smart wearables markets, Fitbit has been battered by Apple’s smartwatch at the high end and cheaper Asian rivals at the low end. Its market share dropped to just 2% in global smartwatches in the first half of 2020, trailing Apple, Garmin, Huawei, Samsung, Imoo, and Amazfit, according to Counterpoint Research.

The new Sense watch marks a return to more full-featured wearables after Fitbit’s original high-end watch, the Ionic, flopped in 2017. The $300 Ionic looked oddly bulky compared to watches from Apple, Samsung, and others and had fewer features. Fitbit had more success with the $200 Versa, released in 2018, and last year’s follow up, the Versa 2, which first added the ability to connect with Amazon’s digital assistant Alexa.

But the Sense may be able to justify its higher price now that it has some features that even Apple has yet to debut, like the skin temperature and electrodermal skin sensors.

The skin temperature readings are taken at night during sleep. Fitbit says trends in temperature can signal signs of a fever, illness, or the start of a new menstrual phase.

The electrodermal sensor, which requires the user to place their palm on the watchface for a reading, likewise can be tracked over time to measure stress levels. A user could measure the level before and after using a meditation app, for example, Fitbit says.

Both the Sense and Versa 3 also correct some major flaws in earlier Fitbit watches, as well. Both have a speaker and microphone to both make requests of the built-in digital assistants and hear responses. Last year’s Versa 2 had a microphone but no speaker. That also means the two new watches can be used via a Bluetooth link to a smartphone to make and receive phone calls, another catch-up feature for Fitbit. And both have GPS built in so the watches can track users’ runs or other exercise activity even if the user isn’t carrying a phone.

Fitbit has sought to bolster its revenue with a $10-per-month premium service that adds more health data analysis and includes exercise and relaxation programs. Buyers of the Sense will get six months of the premium service free and Inspire 2 buyers get one year free.