Walmart introduced a mobile payment feature last year that lets customers use its app to pay at checkout, and now the service is getting close to reaching nationwide availability. As Engadget first reported, the service has just expanded to more than 30 states just in the past two months, including New York and California as of this week. Last year Walmart promised that the service would be available nationwide by the first half of 2016. The Walmart Pay feature lets customers simply use their phone's camera to scan a QR code at checkout, which then triggers a payment in the Walmart app.

Walmart Pay isn't like other mobile payment apps that allow you to pay at lots of third-party stores, but it might not need to be available widely to be successful given how many customers already use the company's app and shop at its stores. Walmart has said it receives more than 140 million customers a week, and that, as of last year, 22 million of those guests use its app every month.