Apple will start making its own chips to enable iPhone apps to run on future Mac computers. But developers say pulling that off may not be so easy. (AAPL)

· Apple announced in June that it will start making its own chips for future Mac computers, enabling its laptops and desktops to run iPhone and iPad apps.
· But that will pose a challenge for Apple's iOS developers, who are used to creating apps centered on touch-based interactions and smaller screen sizes, developers say.
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