According to a study, if you spend much time on your smartphone, it could be an indication of depression. As per researchers at Northwestern University in Illinois, people who suffer from depression spent at least an hour with their smartphones, whereas non-depressed individuals spent nearly 17 minutes on average on a daily basis.

According to the findings, it is possible to detect depression from an individual's smartphone sensor data by tracking the time they spend using the phone in addition to their geographical locations.

According to David Mohr, senior author of the study, "The significance of this is we can detect if a person has depressive symptoms and the severity of those symptoms without asking them any questions. We now have an objective measure of behavior related to depression. And we're detecting it passively".

He added that phones can easily offer some data and a user does not have to put efforts. In order to conduct the study, 28 individuals were recruited by the researchers; the individuals were having an average age of 28 and were followed for two weeks. The participants were told to download the Purple Robot app that "collected their information".

Sohrob Saeb, one of the developers of Purple Robot, said that app helps know if depression can be identified objectively and passively. According to researchers, the app identified individuals having depressive signs with 87% accuracy.

It was also found by the researchers that GPS tracking could assist in detecting mental state of a person.