Apps for Mastering Your Mood Gregor Schuster / Getty Images "How do you feel?" can be a surprisingly difficult question to answer, but new apps are making it possible to track the ups and downs of your emotional weather as easily as EKGs graph heart rate. New fitness devices allow you to track your heart rate, the amount of calories you burn, your skin temperature and even changing electrical conductance on your body, so why not the ebb and flow of mood? A recent poll found that nearly 70% of Americans track at least one physical health indicator and 21% of them rely on some type of app to keep them updated on how they're doing. And since therapists often ask patients to keep track of their changing moods, behavioral triggers and other aspects of their daily lives, it only makes sense that people are turning to tracking programs to help with depression and other mood disorders. Not only does recording data help doctors and patients to better understand why symptoms occur when they do, the information can also reveal relatively quickly whether treatments - including drugs and therapy - are working. MORE: How You Deal With Your Emotions Can Influence Your Anxiety It's similar to monitoring glucose levels at home for diabetic patients, says Dr. Adam Kaplin, assistant professor of psychiatry and neurology at Johns Hopkins University. Kaplin created a texting-based mobile phone program called Mood247 that is now licensed to Remedy Health Media, which has been beta-testing the app for two years with 10,000 people. "If you just measured glucose when you came into a doctor's office, you would provide terrible control for diabetes," Kaplin says. Mood tracking provides the opportunity "to catch up mental health to where our colleagues in medicine have gone for a while." Mood247 texts patients once a day at a time of their own choosing. They reply with a numerical text of how they feel on a scale from 1, which represents their most negative mood, to 10, which indicates their best possible mood. "It's so easy that you can do it in three to four strikes of a cellphone," says Kaplin. Patients can also add descriptions to put their ranking in context. Kaplin currently uses the app with 150 of his patients and just as with many other such programs, the texts can be shared with patients" family, friends or other health care professionals. He's found that the ritual of responding to the texts may be therapeutic, and possibly even live-saving. One woman with bipolar disorder who was distressed after losing her job texted in the annotation, "I'm going to kill myself." Her mother received the message and immediately had her hospitalized. The patient said she had typed in the note rather than avoiding responding to the app's prompt because it had become habit. ""I put my mood in like I brush my teeth or put my socks on,"" she told Kaplin. ""I got my normal text and responded."" Patients who agree to monitoring also know that they will be contacted if they stop supplying the information, particularly if their mood has been trending in a troubling direction. So far, the monitoring is also helping some patients to find useful correlations. Some women have found that their mood changes predictably at certain parts of their menstrual cycle; others find that they are only down when talking to certain people or during the workweek. One of the first successful online mood trackers, Moodscope, was born when its founder Jon Cousins, an advertising agency entrepreneur in the UK, needed a way to track his own mood disorder. Begun in 2007, the site offers both free and premium memberships and now has over 27,000 members. "I was able to see from my graphs that I was going through a rapid cycling pattern, where my mood was quite elevated one day and quite depressed the next," Cousins says, "It's exhausting because you never know where you are - and it's also hugely exhausting for people around you because they never know how you're going to be." Moodscope, which is adapted from a validated mood measure that researchers use in studies of mental illness, asks users to flip and click a series of 20 onscreen "playing cards," each signifying an emotion like "afraid" or "inspired," and containing a rating scale of zero through three to measure intensity. Taken together, the ratings represent a patient's overall emotional temperature. MORE: Viewpoint: My Case Shows What's Right - and Wrong - With Psychiatric Diagnoses In Cousins" case, simply tracking his own moods spurred some improvement. But when a friend asked if he could receive the scores Cousins was recording, his recovery really took off. "When I started sharing my scores, something profound happened," he says. His friend would ask about the scores over email - and that helped him to feel supported and recognize the experiences that were causing him distress. "Suddenly, your low mood isn't always from within and you can see the external factors," says Cousins, who was also helped by talk therapy. Now, Moodscope offers a system where you can share your data with a "buddy" - who can be anyone from a friend to a family member or a therapist. MORE: Rashness & Rumination: New Understanding About the Roots of Depression As useful as mood tracking can be, it can have some disturbing implications for privacy. One free app that works with cellphones, called Emotion Sense, is designed to go beyond the patient's manually entered data and integrates location information as well as how the user tapped into other phone programs such as calls, games and email. Originally developed as a research tool to gather as much information on participants as possible, an earlier version even analyzed voice tone via the microphone as part of its mood assessment, but user feedback suggested that this was too invasive and it was dropped. But Jason Rentfrow, a senior lecturer in psychology at Cambridge University in England, who is helping to develop Emotion Sense, says that mobile phone companies already collect and use potentially revealing data generated by phone users, for commercial rather than therapeutic reasons. Providers gather a lot of this information already [because of] the fine print of the agreements we sign. I'd much rather do it [transparently] and provide access to their own data than [have companies do it] without them fully realizing it. How useful such mood apps turn out to be in mental health therapy won't be clear until more patients try them, and more studies are done on how they affect mood and can be integrated into treatment. But it's hard to imagine that with more people engaged in social media and digital data tracking, that keeping tabs on mood in some way won't be part of mental health care in years to come.