Nepal, Sept. 21 -- Over the past two decades, people across the world have seen digital services transform the economy and their lives. Taxis, films, novels, delivery, noodles and doctors can all be summoned with a tap of a screen. Giant firms in retailing, car making and the media have been humbled by new competitors. Yet, one industry has withstood the tumult-banking. In rich economies, it is perfectly normal to queue in branches, correspond with your bank by post, and deposit cheques stamped with the logo of firms founded in the 19th century.

Technological advances make the current third wave of digital banks look more sustainable. The proliferation and sophistication of smartphones and tablets allow banks to offer many more services ...