The service would be part of the company’s mobile payments service, Apple Pay, and will let users send money to each other instantly—similar to how Venmo works.

Venmo has become enormously popular among a younger crowd to make small, cashless transfers using a phone, like reimbursing a friend for dinner, paying a babysitter, or for paying one’s share of the rent. In the first quarter of 2017, Venmo processed a record $6.8 billion in the first quarter, double the amount from the same period last year.

Forrester Research estimates that the total peer-to-peer payments (P2P) payments market will reach $17 billion in transaction volume by 2019.

This isn’t the first time Apple (AAPL) has been rumored to be working on a Venmo-rival. In November 2015, rumors swirled that the technology giant was developing a mobile P2P service.

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Apple already operates its own digital wallet, Apple Pay, so adding another payments feature might make sense. Apple Pay was launched in 2014 as a way to let shoppers load their credit card and debit card information onto their iPhones in the form of “mobile wallets.”

Customers can then use either their iPhone (or linked Apple Watch) to pay at retail stores equipped with point-of-sale registers supporting near-field communication (NFC) technology, which enables frictionless payments between smartphones and registers. People simply place their phones or watches near the point-of-sale register sensors for a payment to be made without swiping a card. Consumers can also use Apple Pay accounts to pay for items within apps and on the web.

Google (GOOG) operates a competitive mobile payments service for Android phone users, called Android Pay.

Apple is also reportedly in talks with credit card processor Visa (V) to create pre-paid cards that would be linked to a user’s Apple Pay account.