Meet the Vital Scout: a smart patch you can wear discreetly under clothing to monitor your stress, activity, recovery, and sleep all day long. It uses HRV to measure your stress and recovery levels. It can be used to track your activity and sleep level and visualizes the data on your smartphone.
The patch is rechargeable and reusable. The battery lasts multiple days on a single charge. Vital Scout is showerproof. You can pick it up for under $100 at this time.[where to get it]