https://www.cnbc.com/2018/06/09/apple-watch-adds-tech-to-track-parkinsons-disease.html

The Apple Watch will soon be able to track tremors experienced by Parkinson's Disease patients to help them manage their condition.

Later this year, Apple will release a software update to make it easier for medical researchers to understand the difference between a random movement, and the shakes and dyskinesia that Parkinson's patients experience when they're getting treated with medications.