OAKLAND, Calif. (AP) — Longtime Apple executive Phil Schiller on Wednesday acknowledged a court-ordered makeover of the U.S. payment system in its iPhone app store hasn’t done much to increase competition — a shortcoming that could result in a federal judge demanding more changes.

Schiller, who has been overseeing the iPhone app store since its inception in 2008, made the admission during occasionally sheepish testimony about the new payment options that so far have been shunned by all but a few dozen apps since their introduction in January.

“We have worked hard to create this program and I think we need to do a lot more to do to get developers,” Schiller said. “There is work in front of us to make that happen.”

Schiller’s appearance came two weeks into ongoing hearings being held in Oakland, California, federal court to determine whether Apple is properly adhering to an order issued as part of an antitrust case alleging its iPhone app store had turned into an illegal monopoly.