There is and there isn't. The ARM is probably the best processor ever designed (by Steve Furber Sophie Wilson, who are probably reincarnations of Charles Babbage and Ada Lovelace). As such most small and mobile devices that contain a CPU probably contain an ARM CPU. One of its most excellent features is that it is a modular design, the IP rights of which are sold on that basis. You can manufacture an ARM under copyright but bolt your own bits on and omit others (and not pay IP rights for those) depending on your needs. There are special power management bits, floating point bits, graphics bits. You can have a basic, cheap CPU for disposable devices to an all-singing, all-dancing CPU for performance devices. Apple has been using the ARM since the Newton. Its modular design means that Apple has been able to commission an ARM with extra bits of its own design bolted on. So yes, it is an ARM. And yes, it is Apple's own, proprietary design also.