The popularity of the messaging app WhatsApp is booming, with it reaching a record-breaking one billion monthly users for the first time ever. Since the service was acquired by Facebook in 2014 it has gone from strength to strength, with 42 billion texts and 250 million videos being sent by the service each day. The lack of usage fees is a massive selling point for WhatsApp, and mobile users have flocked to the service, especially when speaking to people internationally. Jack Kent, mobile...