RationalFX and Xendpay founder Rajesh Agrawal on Apple Pay, Masai warriors and the future of banks

When I get the Tube, I always pay using my Apple Watch,” says Rajesh Agrawal. The Indian-born entrepreneur and philanthropist doesn’t exactly need to take the Jubilee Line to work – in The Sunday Times Rich List 2012, he was estimated to be worth around £90m. But making money has never been the aim: “look at Beckham – he started playing football because he loved the game, not money. Money can never be your goal; it is a by-product.”

Ten years ago, Agrawal was sleeping on someone else’s sofa because…