https://www.theverge.com/2018/7/5/17537324/apple-app-store-stats-10th-anniversary

Apple revealed several new numbers today in a report celebrating the App Store’s 10th anniversary, including details about subscription apps.

ResearchKit and CareKit, Apple’s software tools for doctors and medical researchers, are getting used in clinical trials for conditions including physical therapy, Parkinson’s disease, and autism. The report notes that over 500 doctors and scientists have used the tools and 3 million people have participated in such trials.