'Dynamic pricing' means prices can quickly adapt to reflect changing levels of supply and demand. When Uber, a private New York-based taxi service trialled the idea, some customers were charged over $80 per mile, causing widespread anger.

In a smartphone-centric society, fluidity and unpredictability have become the norm. People are accustomed to living by their own schedules, and on their own terms. Enter YPlan, an app that takes the hassle out of having to plan ahead.

With 2 million users, a deal with Starbucks, and $6 billion worth of transactions, Square is turning smartphones into checkouts, digitising loyalty schemes and reshaping how consumers spend – without using NFC technology.

In societies that are cash-rich but time-poor, gift cards have emerged as a popular solution. The gift card market in the UK alone is currently worth £4bn; and with smartphone penetration rising, gift cards are becoming digital.