Thessai’s bundle of motion sensors and panic buttons alongside the monitoring app. (Thessai Photo)
Thessai , a Bellevue, Wash., startup led by a former Microsoft HoloLens executive, is rolling out a home monitoring system for older adults that flags trouble without cameras, microphones or wearables.
Motion sensors placed around the home feed Thessai’s AI software, which learns a person’s normal patterns over time, such as when they wake up, how often they use the bathroom and how much they move around. The system then sends an alert through a mobile app when something falls outside that baseline: a long stretch of inactivity, unusual movement at night, or a front door opening at 2 a.m.
Founder and CEO Michael Nassirian started the company after his mother-in-law fell at home and was injured. She had a phone and an emergency button within reach but didn’t use them, and she told no one until the next day, when she needed an ambulance.
The family looked for a way to keep tabs on her and found only wearables and cameras, which she refused. So Nassirian bought motion sensors at Home Depot, put them around her home, and wrote software to alert his wife if her mother stopped moving.
Keeping quiet about a fall or health scare is common among older adults, Nassirian said.
“Number one, they say, ‘I’m OK.’ Number two, ‘I don’t want to bother you,’” he said. “And number three, and most important, is embarrassment. They do not want to advertise it.”
Pendants and smartwatches with fall alerts have long been the default, but they only help if people use them. A review of nearly 120 fall-detection studies co-authored by a University of Alberta researcher found that older adults who fall often don’t use their devices to reach a caregiver. Thessai joins a crop of companies pitching camera-free ambient monitoring instead, including Cherish , which makes radar-based sensors, and Butlr , which uses thermal heat detection.
Nassirian spent nearly two decades at Microsoft, working on Office, Windows and later HoloLens, where he was a partner quality architect. Before that, he spent about 14 years at Texas Instruments in test engineering. He has a master’s in biomedical engineering from the University of Texas at Austin, and since leaving Microsoft he has founded and advised several startups, including ARVR Academy and Predictive AI Research.
Michael Nassirian at Seattle AI Week at Kiln in Fremont, where he was unveiling Thessai’s technology. (GeekWire Photo / Kurt Schlosser)
After relatives started asking for monitoring systems of their own, Nassirian formally founded Thessai in 2024 and has self-funded it so far. The company sells two packages, Basic and Premium, to families with an older relative living alone. Its Enterprise package gives senior-living operators a dashboard for monitoring multiple residences.
The Basic package , which includes motion sensors and a hub that plugs into the home’s Wi-Fi, costs $195 plus a $38 monthly subscription. Premium adds features such as a panic button and two-way voice check-ins through the hub, and costs $249 plus $59 a month. The sensors run on batteries that Nassirian said last at least a year and a half.
Nassirian said independent-living communities have been the strongest market so far. Memory-care facilities already have staff watching residents closely, he said, while independent-living operators are pitching Thessai to renters as a “smart home” feature.
Nassirian said the older adult decides what gets monitored. Through the app, they can switch off sensors in certain rooms, the bathroom for example, and limit tracking to the kitchen and living room. Caregivers can also tune alerts to cut down on noise, so a parent who routinely sleeps late, for example, doesn’t set one off.
“We designed it to the last bit of the person’s privacy,” he said.
Thessai is going after a large and growing market. Older adults overwhelmingly want to stay in their homes (75%) and communities (73%), according to AARP’s 2024 Home and Community Preferences Survey , and households led by people 80 and older are set to double by 2040.
The startup soft-launched in May and has a few hundred customers, split between families and senior-care operators, Nassirian said. Its advisory board includes Chuck Lytle, who founded Bellevue-based senior housing companies Lytle Enterprises and Leisure Care.
Nassirian said the company is also working with the Department of Veterans Affairs on bringing the system to veterans, including in rural areas, with the option to run it on the VA’s own secure network.
Thessai has four employees in the U.S. and seven in Singapore. Nassirian is now looking to raise outside money, mainly to buy hardware in larger volumes and bring down per-unit costs.
Longer term, he wants to do away with the physical sensors altogether and detect movement from a home’s existing Wi-Fi signals, an approach researchers at Harvard and Carnegie Mellon are studying.
“I’m in technology,” he said. “I’m not going to sit still.”
