You can't nail the perfect squat with just an iPhone app
 

The Squat. Capital 's'. With or without weight, it's widely regarded as the best exercise you can do. But one that's easy to get a little bit wrong and ruin all those benefits. So here's Kaia Health's Perfect Squat Challenge app, developed with input...

https://www.engadget.com/2018/06/27/...pp-ai-trainer/