Stryd

Stryd is a wearable that aims to help runners optimize their exertion levels thanks to the device's multiple sensors for motion, temperature and humidity. The wearable, which straps to the runner's shoe, can detect headwinds and tailwinds during a run and provide feedback to the runner. It can also track speed, running form, fatigue and slope level as well as sync with several smartwatch models. The wearable is available for $219.