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Starbucks and Square, one-time partners in mobile payments, are going their separate ways in the ongoing battle for how to order and pay for items using smartphones.

Square’s Wallet app stopped working at Starbucks last week, ahead of Square’s plan to stop supporting the app early next year. In an email to users last week, Square said it is discontinuing Wallet to transition to Square Order, a new app to let consumers place orders in advance of showing up at stores.

Starbucks won’t accept payments from the new Square app because it is testing its own app to allow users to pre-order drinks before arriving in shops, building on its loyalty program and its own successful mobile-payment app.

Square said in May that it was going to discontinue Wallet eventually in exchange for Order, but it had continued to support Wallet even after pulling the app from Apple’s App Store and Google Play.

Starbucks and Square teamed up in late 2012 to provide consumers with the option of paying for food and drinks using a barcode within Square Wallet. It never took off as a way to pay for items in Starbucks, due in part to the popularity of the coffee retailer’s own app that accounts for the bulk of mobile payments at its stores.

In October, Starbucks CEO Howard Schultz said about seven million transactions per week, or about 16% of those in U.S. stores, were being done on mobile devices.

Square and Starbucks are not totally splitting up. Square said it still processes debit and credit card payments at 7,000 of the coffee chain’s U.S. stores.