Since 2014, Harvard University has been running the Football Players Health Study, a program that examines the well-being of former NFL athletes as they leave the game behind. Now, as part of its ongoing research, the Ivy League college developed an app called TeamStudy, which uses simple physical activities, surveys and sensor data from an iPhone to learn more about the state of a player's health.

The collected data comes together in one place thanks to Apple's ResearchKit, and Harvard researches say ex-NFL players helped design the iOS application, as they wanted it to focus on important issues including balance, memory, mobility and pain, to mention a few.