Enter the mobile application, or “apps.” They track mood with fill-in surveys, provide positive thinking briefs, provide medicine reminders and even make cognitive treatment into a game.

The medical community is on board with the concept. The tools of an app can be used to screen potential patients, instead of having them search for a qualified clinic and undergo extensive testing. It’s also a way to reach an underserved population in teenagers, who are huge mobile phone users but whose mental disorders aren’t typically discovered fast enough. After all, suicide is the third-leading cause of death for those aged 15 to 24, which is prime cell phone use territory.

A SelfEcho survey of clinical psychologists discovered that 73 percent of respondents believe software that collects and aggregates data on patients would be valuable in tracking patient progress. Of those, about 68 percent believed that using more data in their practice would help them treat patients.

The biggest benefit of mobile phones is the ability to detect real-time changes in behavior, an indicator that can use the data to see where things may be going off track. A Dartmouth College app collected audio, motion and location data from 48 student volunteers for 10 weeks. The data collected correlated with changes in depression, stress and loneliness that was revealed in student surveys. The app’s data reveals details like physical activity, places visited, communication, sleeping patterns and the likelihood that someone has engaged in a face-to-face conversation.

We are at the very beginning of this brave new world of app psychology. In the future, the data collected may be used for early interventions on patients who may be non-compliant with medications, for one example. It is also not far-fetched that alarms may sound for patients with diagnosed depression who may significantly alter their daily habits in ways that signal trouble.