Fighting for marketshare in the mobile wallet space is not getting any easier.

According to a recent report, Apple tops the charts with its digital wallet, and is expected to nearly double Apple Pay userbase this year. The study, released by Juniper Research  this week, estimates that Apple Pay will hit 86 million users in 2017 globally, up from 45 million in 2016.

Apple Pay, Samsung Pay, and Android Pay — the largest mobile wallets out there — will together sign more than 150 million users by the end of the year, with Apple Pay users making up about 57% of that market. The combined market share of Apple, Samsung, and Google (via Android Pay) is expected to reach 56% of total mobile contactless payments by 2021, the study suggests, with their combined userbase exceeding 500 million.

“The research found that Apple Pay, and the alternative wallets that have followed in its wake, are set to establish themselves as the primary contactless mechanisms of choice in the US. However, the challenge facing Apple and its rivals is to ensure that the infrastructure is in place for consumers to make in-store payments,” according to the report.

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