Google, facing antitrust scrutiny, says it will let apps like Spotify offer alternate billing systems.

Some apps, such as Spotify, will be able to offer their own billing system in the Google Play store as part of a pilot program.

The move would allow those apps to use their own payment system. The change comes as the two biggest app store operators face complaints from regulators and developers that they are abusing their dominance in mobile software to force companies to use their proprietary billing methods.

The test program will begin with a music streaming service. The payment system offered by the Google Play store will not be the same as the billing system offered by Spotify.

This is a significant milestone and the first on any major app store, wrote Sameer Samat, a Google vice president who oversees the Google Play store.

In its own post announcing a multiyear agreement, it said it supported platform fairness and was expecting the billing option to become available later this year. The company filed a complaint with European regulators against Apple, arguing that the company used its dominance in the app store to hurt competitors.

In South Korea, a law banning app stores from forcing developers to use their proprietary billing systems was passed last year.

The test program is likely to cut away at the lucrative commissions that are charged to app developers. For a long time, Apple and Google took a 30 percent commission on the sales of digital goods in their app stores. As a result of the uproar from developers and scrutiny from regulators, both Apple and Google have lowered their commissions for smaller developers.

Even if users don't use the billing system, the company will still get a service fee, even if they don't, as it already does in South Korea, according to Dan Jackson. He said that the pilot had just begun and that the company would work with partners to figure out the details.

Last year, as part of a legal settlement, Apple said it would allow a set of apps, which provide digital media like books, newspapers, music and video, to steer customers to their own websites to pay for subscriptions.