A new mobile phone app is aiming to give young people experiencing mental health issues some hope.

The app is the creation of Headspace, a national youth mental health foundation, which specifically targets young people with mental health issues.

Titled "The Fifth Army" the app is about engaging young people between the ages of 18 and 25.

It focuses on three main issues of concern for that age group, bullying, homophobia and depression.

Headspace chief operating officer Chris Tanti says the mobile app is the ideal way to get young people engaged with the issues and to help them recognise the symptoms and signs.

"The campaign is unique in directly addressing three massive issues and delivering it to young people in the mediums they feel most comfortable with," he said.

The app is broken up into those three categories and once downloaded participants chose which category they want to follow.

They are then led through a series of missions, which revolve around answering questions or completing exercises on that subject.

Mr Tanti says with suicide being the leading cause of death among Australians under the age of 25, getting the message out about mental health is vital.

"We do know that young people are struggling in silence and they're completely isolated, " he said.

"The longer these things go on or occur without assistance, other problems emerge so people can then use alcohol as well as a way of medicating against symptoms."

Anyone experiencing mental health issues or knows someone who is should contact Lifeline, 13 11 14.