Monzo — the popular app-based bank known for its trademark coral-coloured debit cards — is launching a competitor to mobile networks EE, O2, Three, Sky Mobile, and Vodafone, to name just a few. Unlike its closest rivals, phone plans from Monzo are designed to get cheaper every year. Yes, really . The bank, which boasts more than 15 million customers worldwide, said its SIM-only plan challenges the traditional model by rewarding long-term loyalty. This is in contrast with traditional networks, wh