Running with an AI 'personal trainer' is fun, but expensive

It's a question that I've been musing about ever since I started testing Vi, which its creators call the "first true AI personal trainer." It combines a pair of bio-sensing headphones and an app from Lifebeam, a military biosensor company founded by a pair of former Israeli air force pilots. Lifebeam's side hustle is to take those same sensors and bake them into consumer products like cycling helmets and baseball caps. Here, the company has added that technology to a pair of Bluetooth earphones, along with a raft of other fitness tracking equipment. Buried inside the "halo" that sits around your neck is a six-axis gyroscope, barometer and accelerometer.