The U.S. Justice Department is reaching out to parental app control companies that may have been affected by Apple’s allegedly anti-competitive App Store practices.

Reuters reported this morning that Suren Ramasubbu, the chief executive developer of Mobicip, was interviewed by US investigators. Mobicip, which allows parents to control what kids access on their iPhones, was kicked out of the App Store last year because it failed to meet new app requirements.

Revelations that the FBI has access to a tool that can unlock data on secure iPhones are raising questions as to why the agency is demanding Apple help to create a “backdoor” to recover data on the iPhones of a Florida shooting suspect.

President Donald Trump called on Tuesday for Apple to “step up to the plate” and “help our great country” by unlocking the iPhones used by a Saudi aviation student that killed three people at a Florida Navy base in December.

Apple denied late Monday that it has not cooperated with U.S. federal authorities to help unlock a pair of iPhone’s believed to have belonged to a Saudi aviation student that killed three people at a Florida Navy base in December, saying it always works with law enforcement in their investigations and directly contradicting claims by the U.S. Attorney General that it had not given “substantive assistance.”

Apple could be headed for another collision course with U.S. federal law enforcement, similar to the spat it had with the FBI over creating backdoors into iOS.

Attorney General William Barr has asked Apple to provide access to two phones used by the gunman at the Pensacola Naval Air Station shooting last month. Barr said this morning that Apple has provided no “substantive assistance” so far and indicated that he’s ready for a fight regarding the issue.