Starbucks is edging out Apple and other competitors in the proximity mobile app sector with 23.4m US people aged 14 and over expected to use the app to make a point-of-sale purchase at least once every six months in 2018.

The coffee chain has found enormous success in the mobile payments space, largely down to the fact its app ties payments to its loyalty program. The 23.4m users in 2018 puts it slightly ahead of Apple Pay’s 22m users in 2018, according to eMarketer. Meanwhile, Google Pay and Samsung Pay remain off the pace in terms of adoption with 11.1m and 9.9m users this year respectively.

 “The Starbucks app is one of the bigger success stories in mobile proximity payments,” said Cindy Liu, forecasting analyst at eMarketer. “It has gained traction thanks to its ability to tie payments to its loyalty rewards program. For users of the app, the value of paying with their smartphone is clear and simple—you can save time and money at the register, all while racking up rewards and special offers.”

Looking ahead, it’s expected that Starbucks will reach 29.8m users by 2022, keeping it ahead of Apple’s 27.5m, Google’s 14.9m, and Samsung’s 13.2m.

Despite user numbers continuing to grow amongst the top four proximity mobile payments apps, their share of mobile payment users will gradually continue to fall as new payment apps enter market.

Overall, the number of proximity mobile payment users in the US will grow by 14.5 per cent this year, reaching 55m. In addition, this year will over 25 per cent of US smartphone users aged 14 and over will make a proximity mobile payment at least once every six months.