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The app, developed by digital agency Jam, is the "first of its kind", according to the charity, and "provides an online safety net, reducing the chances of a person's call for help being missed". It is free and can be downloaded across the world from Wednesday.
Given the popularity of Twitter around the world – the micro-blogging site has 284 million monthly active users – and particularly among younger people, it is little surprise Samaritans is collaborating with the tech company. The app is targeted at Generation Y –those between 18-35 – who grew up with technology, and are the most active age group on social media.
The charity cites research published in 2013 by Crisis, which identified an association between rates of Tweets per users determined to be at risk for suicide, and actual suicide rates. "It therefore identified Twitter as an important surveillance tool for detecting suicidal patterns," the charity added.
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Joe Ferns, executive director of policy, research and development at Samaritans, said it was important to make the online environment safer for vulnerable people.
"By not addressing this issue we run the risk of shutting these discussions down and driving them underground. Instead we need to use tools such as Samaritans Radar to encourage people to look out for one another online, helping them to reach out and offer support," he said in a statement.
It's not the first time that technology has been applied to help people with mental health issues.
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The American app PTSD Coach is targeted at people suffering from post-traumatic stress disorder – particularly veterans – with the aim of helping them "learn about and manage symptoms that often occur after trauma". It has been downloaded more than 100,000 times across 74 countries.
Meanwhile, researchers at the Center for Behavioral Intervention Technologies, at Northwestern University Feinberg School of Medicine, are working on both mobile-phone and web-based interventions. One such app was Mobilyze, which tracks users' moods and alert them at "critical moments" in an effort to reduce depression.