The app lists the "warning signs" to look out for in cases of forced marriage and so-called "dishonour-based violence".
At the touch of a button, the user can also be directed straight through to the emergency services.
Aneeta Prem, founder of Freedom Charity, said:
"We listened to young people and took action when they told us they would prefer information to be communicated to them by way of an app. In accessing the Freedom app, the user is just two clicks away from getting life-saving help. It's the 999 of apps and we urge everyone to download it, for free, today."
A new smartphone app, for young people at risk of being forced into marriage, has been launched today by Freedom Charity, the Government's Forced Marriage Unit and the Metropolitan Police.
The app has been designed to reach out to young people, aged 16 to 25, who are most at risk from forced marriages. It looks like a game, making it attractive to use and helping to avoid suspicion from parents. But the charity says it contains information which could be "life-saving".
Watch Freedom Charity's video about the new app below.