In N-of-1 trials, researchers often work closely with computer scientists to design smartphone apps that do everything from tell the participant which treatment to try, remind them to do it, collect data on whether those treatments are working, and analyze that data in real time.
Although you don’t need to use a smartphone app to create an N-of-1 trial, it does make the process a lot easier.
Above is an example of an N-of-1 trial for improving sleep. This person is experimenting with wearing earplugs to bed. The N-of-1 app collects data on the effectiveness of this approach, as well as other factors that might have affected the person’s sleep that night.