US regulators are considering an inquiry into whether Apple violates antitrust law by requiring that its programing tools be used to write applications for the iPad and iPhone, a source familiar with the matter has now said.

The news comes amidst a high-profile dustup between Apple and Adobe Systems, which makes the widely used Flash software to provide video and build games.

Apple CEO Steve Jobs... his comments on Adobe's Flash may be put under the regulators' spotlight.

Although Flash is nearly ubiquitous on the internet, Apple calls it a balky battery hog and Apple chief executive Steve Jobs will not allow Flash on the iPhone or iPad, or as a tool to build apps on those devices.

Apple has sold more than 50 million iPhones since its debut in 2007, and one million iPads since its April 3 debut. The devices' popularity means extra scrutiny about every Apple move related to the smartphone platform.