In 2002, as he made his way home to Canada from a holiday in Tunisia, Arar was detained in the US and held without charges in solitary confinement by authorities which suspected him of being a member of Al Qaeda. After two weeks, he was deported to Syria, where he spent almost a year, during which time he was tortured, according to a commission of inquiry ordered by the Canadian government.

Arar was later cleared by both the Syrian and Canadian authorities of any involvement in terrorism and received C$10.5 million for what Canada's then prime minister Stephen Harper called his "terrible ordeal".

Now Maher is hoping to put some of the money to use through a platform called CauseSquare, which promises to help bring charitable work into the digital era. The app will act as a one-stop shop for charitable activities, where people can scroll through participating charities, which will be grouped based on their area of interest.

The platform will facilitate donations but also lets NGOs send out push notifications, short bursts of text or video designed to grab the attention of the Facebook generation, while a volunteer section will let people reply to requests to provide help in the form of time and effort.

Speaking to Finextra about the venture at the Payments Panorama conference in Calgary last week, Maher was clear that he has lofty ambitions, insisting that he eventually wants build a service that acts as the Amazon, Facebook, Twitter and Eventbrite of good causes.

He says that CauseSquare's research shows that young people are politically engaged and willing to give their time and money. However, millennials tend to be wedded to causes rather than organisations and live in a mobile society that NGOs have been slow to adapt to.

Borrowing from the Amazon playbook, the CauseSquare app will let users give charities a star rating, while a gamification element will let people earn points for good deeds - from simply sharing a charitable appeal on social media to making a donation or volunteering 20 hours of their time.

This is no gimmick, says Maher, who notes that young people already regularly talk about their charitable work on their resumes and could be eager to have a 'score' that can be shared with not only friends but potential employers.

Maher says that his own experiences have prompted him to try to good in the world, but CauseSquare is a for-profit enterprise that plans to charge charities to use the app, offering a tiered payment plan that sees them pay rates dependent on how many push notifications they are allowed to make through the app and how many donations they can accept through it.

Maher says he hopes to show that the app earns participants 10 times as much as they pay.

Interest has been positive, although the firm is deliberately targeting NGOs with younger fundraising managers who 'get' the digital world. So far around 45 charities - mainly in Ottawa - have signed up with about 15 working as active beta testers.

As well as paying a fee, charities will be encouraged to market the app to their donor bases, something which Arar concedes some are resistant to. Meanwhile, CauseSquare is planning to enlist its own ambassadors on places like university campuses and to use social media. And, of course, Maher hopes that his own, terribly earned, celebrity will help him to advance his giving cause.