A new study has showed that smartphones can help figure out if the user is under depression. The study was published in the Journal of Medical Internet Research. Researchers tracked 40 people aged 19 to 58 for two weeks and found that the participants who spent a lot of time using their phones and those who stayed in one place for long durations exhibited depressive symptoms.

The researchers identified subjects with depressive symptoms with 87% accuracy with the help of phone data and GPS tracking. The study’s lead author, Northwestern University’s David Mohr, said although the study was small scaled, it provides a way to monitor mental well-being of people in a measurable and objective way.

Mohr is also the director of the Center for Behavioral Intervention Technologies at Northwestern University’s Feinberg School of Medicine. He continued that social withdrawal, sleep disturbance, lethargy and lack of concentration are the signs of depression. Cellular devices can provide information about such behaviors to families, caregivers or physicians.

The study found that depressed individuals used smartphones for 68 minutes, whereas no-depressed individuals used it for about 17 minutes.

“People are likely, when on their phones, to avoid thinking about things that are troubling, painful feelings or difficult relationships. It’s an avoidance behavior we see in depression”, said Mohr.

Spending longer periods at home and visiting fewer places suggest both lethargy and social withdrawal, which are linked to depression.

Researchers have developed an Android app, called Purple Robot, to help store and forward data collected by most cellphones.