A Scottish firm is suing Apple over claims the computer giant illegally used patented technology on the iPhone and iPod Touch devices.
Glasgow-based Picsel Technologies filed its US lawsuit at the Delaware District Court.
Picsel claims Apple used a key component from one of its mobile rendering patents. The component allows users to scan through on-screen content without experiencing long screen update delays.
Picsel wants compensation for the Apple units already sold, unspecified damages and legal fees.
Picsel claims Apple users could be subjected to prolonged delays while zooming into and panning documents, web pages and images without using the technology.
Apple has not commented on Picsel's legal action.