Using just a heart rate monitor and accelerometer? Sounds like crap to me.
Measure my gait using one set of sensors, that can be placed in different locations around the body, but, the device has no idea where it is in relation to my legs? Really? Today the phone is in my coat pocket, and I'm walking on a flat pavement, tomorrow my jeans pocket as I walk through the woods. Any meaningful comparison in those two sets of data?
Sounds more like some medical institutions are counting large, unrelated, donations to some research projects made by some anonymous Californian technology company. Allegedly.