Apple Pay has 30.3 million users, up 38% from estimates last year, followed by Starbucks with 25.2 million, up 8%, market research firm eMarketer said in new report on Wednesday. The firm released its previous estimates in May 2018. For this year, Google Pay trails in third place with 12.1 million users, up 9%.

Apple Pay, introduced in 2014, has received a big lift by being the only general mobile payments app available on iPhones. It grew slowly initially and angered some retailers like CVS and Best Buy that pledged not to accept the iPhone-based system as they tried to develop a competing system.

But as payments rivals, like the retailers’ effort CurrentC, have fallen by the wayside, more stores are now accepting Apple Pay. That includes one-time opponents CVS and Best Buy.

Starbucks, one of the first retailers to create its own mobile payments app, has seen its growth limited since its app is only usable in its own stores—and it’s no longer opening new stores across the country at a rapid pace.

Apple Pay now looks like another example of Apple introducing a ground-breaking if flawed product and slowly improving it over time until it becomes a market leader. Other examples include the Apple Watch and the iPhone itself.

About 70% of U.S. retail stores will be equipped to accept Apple Pay and similar mobile payments apps by the end of the year, eMarketer said. Because credit card companies are shifting to chip-based cards, many retailers have had to upgrade their checkout systems. Those new readers also accept payments from smartphones using a wireless standard known as NFC.

Meanwhile, Google Pay has been at somewhat of a disadvantage because it shares its presence on Android phones with rivals, such as Samsung. Android users, therefore, have greater choice.

“Apple Pay has benefited from the spread of new point-of-sale systems that work with the NFC signals Apple Pay runs on,” eMarketer principal analyst Yory Wurmser noted in the report. “The same trend should also help Google Pay and Samsung Pay, but they will continue to split the Android market.” 

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