Some £600bn is sent home every year by overseas migrant workers, almost four times more than all the countries of the world combined spend on foreign aid. But far from home, many workers fear their families are not spending their money in the right way. World Hacks looks at a two possible solutions for giving them more control over how their hard-earned cash is being used. Presented by Sahar Zand. Image caption: 1000 peso bills in the Philippines / Image credit: Joel Nito, Getty Images.