Following the acquisition of PA Semi last year, Apple is looking for yet more microprocessor design expertise to work on future chips for the iPhone and iPod touch. The company has been hiring engineers with the hope that its proprietary designs may be able to give its devices unique and exclusive features that its competitors will not be able to replicate. Among those recently signed up by Apple are Raja Koduri and Bob Drebin, both former CTOs of AMD’s Graphics Products Group, along with longtime IBM executive and chip expert Mark Papermaster.

Though it’s well known that Apple already plays an active role in the design of chips from third-parties, switching to an in-house strategy boasts the huge advantage of secrecy. This will allow them to take their designs directly to a chip foundry without disclosing any plans with other mobile processor manufacturers, so that it can prevent feature leaks and better differentiate its handheld products from a growing list of competing devices. The fruits of the move won’t likely be seen until at least next year and should focus on, among other things, lowering power consumption and improving the graphical abilities of Apple’s handheld products.