Aura at CES 2019 introduced an Apple Watch "Smart Strap" designed to measure weight, water, fat, and muscle via electrodes built into the band. The strap didn't end up launching in 2019, but Aura says that it's set to launch in March 2020, with pre-orders available now.
The Aura Strap, which is priced at $99, claims to allow users to measure their body composition and track their hydration...