Contactless payments — secure wireless transactions aided by NFC — are gaining on magnetic swipe and chipped cards at retail establishments, according to the financial technology analysts at Juniper Research, and mobile devices can be thanked for the unexpectedly speedy transition. Juniper estimated today that “OEM Pay wallets” will account for one in three in-store payments by 2020, led by Apple’s platform Apple Pay.

Though card-based transactions are expected to keep dominating the market over the next two years, contactless payments have surged in popularity: They are expected to exceed the $1 trillion mark for the first time this year, one year ahead of Juniper’s prior forecasts, and reach $2 trillion in stores by 2020. That represents only 15 percent of total point-of-sale transactions across the world, but is up from basically nothing less than five years ago.

The key driver for the growth is the digital “Pay” wallet concept developed by smartphone makers. Apple Pay, Samsung Pay, and Google Pay are leaders worldwide, while Huawei Pay and Fitbit Pay have launched in several markets, and Xiaomi and Garmin also offering limited solutions. By 2020, Juniper expects that there will be over 450 million people using these digital wallets, and Apple’s users will constitute half of them. Growth is currently strongest throughout Europe and the Asia-Pacific region, including China, where cardless transactions are really taking off.

Growing adoption of contactless readers clearly has had an impact, as well. Square introduced its first standalone contactless device reader in November 2015, and other retail payment terminal makers have phased the technology into their devices over the past several years.

Contactless ticketing is predicted to be another major benefit of the digital wallets. Juniper forecasts that there will be 10 billion contactless ticketing transactions on mobile devices by 2022, including both purchases and validations. North America is expected to lead the growth of mobile device-based ticketing, followed by China and the Far East region.