Actually it takes a minute to put four sensors on and calibrate your posture before class. I’ve used it since my gym shut down in March, and do not plan to return there any time soon. This sensor kit with the free app with cool classes totally transformed my practice with respect to the depth, focus and effectiveness. Imagine having a private teacher who is paying attention to you, measuring your posture in Asana, gives you immediate feedback and praises you when you do it right... and it costs a fraction of $ you would pay for your private session. None of the big fitness brands come even close to this technologically. It’s a future of home yoga practice whether some may resist “invasion” of tech in yoga or not.