According to a study by researchers at Northwestern University Feinberg School of Medicine, depression can be detected from smartphone location and usage data.
Spending most of your time at home and most of your time in fewer locations, as measured by GPS tracking, can indicate depression.
"We now have an objective measure of behavior related to depression. And we´re detecting it passively. Phones can provide data unobtrusively and with no effort on the part of the user," says researcher David Mohr.