Scientists have developed a smartphone app that can help you figure out what triggers your mood swings.
The Emotion Sense app created by a team led by Cambridge University is being credited with having implications for psychological therapy.
The app uses sensors on your phone to collect information about where you are, how active you have been and who you have been speaking to, for example.
This data is cross-referenced with information keyed in by the user giving an overview of their feelings which is refined by a survey.
"Most other attempts at software like this are coarse-grained in terms of their view of what a feeling is," said Dr Jason Rentfrow, senior lecturer in the university's Department of Psychology and a research team member.
"Many just look at emotion in terms of feeling happy, sad, angry or neutral. The aim here is to use a more flexible approach, to collect data that shows how moods vary between people. That is something which we think is quite unique to the system we have designed," Rentfrow said.
The designers of the app hope it will throw up a spot-on record of what provokes people's highs and lows.
"Behind the scenes, smartphones are constantly collecting data that can turn them into a key medical and psychological tool," team member Dr Neal Lathia, a research associate at Cambridge University's Computer Laboratory, said.
"Any smartphone now comes with numerous sensors that can tell you about aspects of your life, like how active you are, or how sociable you have been in the past 24 hours.