Concerns about the competitive impact of Apple's developer rules have spread to Europe.
Already facing several inquiries from U.S. government agencies, Apple has a new group of regulators to worry about.
Officials from the European Union have joined a Federal Trade Commission inquiry into Apple's developer rules that began several months ago, according to a report in The New York Post.
European Commission investigators have reportedly teamed up with FTC investigators in an attempt to determine whether Apple's rules for iOS developers harm competition.
A spokesperson for the FTC did not immediately return a call seeking comment.
In May, the European Commission published a Digital Agenda, which among various policy goals calls for technology products and services "to be open and interoperable."
Apple's rules, laid out in a beta version of its iPhone SDK Developer Agreement in April, were worded so broadly that they seemed to forbid the use of most third-party development tools, such as Adobe Flash, Unity Technologies Unity3D , and Ansca Mobile's Corona, to name a few.
In an unusual public letter, Apple CEO Steve Jobs explained his disdain for Flash and made it clear that he believes cross-platform development tools in general make developers dependent on those tools, produce substandard software, and limit the ability of developers to deploy new platform innovations.
(Apple could mitigate this problem by sharing platform enhancements with third-party toolmakers under a non-disclosure agreement in advance of general release. This would allow toolmakers to update their products and release them in concert with Apple's iOS and hardware updates. But the company chooses not to do this.)
Stung by Jobs's rejection, Adobe and developers complained loudly. The uproar prompted interest from the Department of Justice and the Federal Trade Commission, with FTC ultimately helming the inquiry.
When iOS 4 was released, the world did not end as some developers feared it might. Games created using third-party tools continued to be accepted.
It has become clear that Apple is primarily interested in keeping apps created using Flash off iOS devices, though Apple could enforce its restrictions more broadly if it wished.
Concerns remain that Apple's rules will affect the ability of developers to utilize third-party metrics tools and advertising technology in their apps.