The most popular media tablet nowadays, the Apple iPad, was originally supposed to be powered by one of Intel's low-power Atom microprocessor and not an ARM-based system-on-chip. Nonetheless, Apple's top executives convinced Steve Jobs that ARM was a better choice, something that eventually created a strategic inflection point for Apple.

Steve Jobs' biography by Walter Isaacson (Amazon, B&N, iBooks), reveals that Steve Jobs and Jonathan Ive (vice president of Industrial design at Apple) started to develop the device in the first half of last decade and even their patent applications revealed sketches of the iPad back in 2004. While the sketches from 2004 clearly resembled iPad from the outside and somewhat reflected the touch-screen-based operating system, the insides of the tablet remained a mystery.

Since Apple decided to transit to Intel's x86 chips in 2005, Mr. Jobs planned to use low-power Intel Atom microprocessor inside the iPad initially. However, Tony Fadell, the senior vice president of the iPod division at Apple, insisted that the iPad would be ARM-powered although Mr. Jobs insisted that it was "best to trust Intel to make good mobile chips". The history knows what happened next: Apple bought PA Semi chip designer, which created the A4 system-on-chip for the company. Apparently, Steve Jobs was pretty pleased with the result and even told his biographer that Intel was anyway too slow and not too flexible to offer something comparable.

"At the high-performance end, Intel is the best. They build the fastest chip, if you don't care about the power and cost. But they build just the processor on one chip, so it takes a lot of other parts. Our A4 has the processor and the graphics, mobile operating system, and memory control all in one chip. We tried to help Intel, but they do not listen much. We have been telling them for years that their graphics suck. Every quarter we schedule a meeting with me and our top three guys and Paul Otellini. At the beginning, we were doing wonderful things together. They wanted this big joint project to do chips for future iPhones. There were two reasons we did not go with them. One was that they are just really slow. They are like a steamship, not very flexible. We are used to going pretty fast. Second is that we just did not want to teach them everything, which they could go and sell to our competitors," Steve Jobs told his biographer.

Meanwhile, Intel's chief exec Paul Otellini said that Apple and Intel could not agree on the price and on who would control the development. Apparently, Mr. Jobs demanded too much control over design of the x86 iPad chip.

Although the price might not be right for Apple, the advantages of ARM-based A4 and A5 are rather clear: lowest-possible power consumption, high-performance low-power PowerVR graphics core as well as ability to tailor the chip for the iOS and vice-versa. On the other hand, an x86 would allow to develop much more demanding applications for the iOS or even launch Mac OS on tablets providing more features to interested users. Both approaches have their pros and cons and Apple has chosen to go with ARM in order to appeal to consumers looking forward long battery life to consume content and in a bid to and to control everything from the sketches of the silicon to final touches of device itself.

"The reason why Apple can create products like the iPad is that we have always tried to be at the intersection of technology and liberal arts," said Steve Jobs.

Tags: Apple, iPad, iOS, Mac OS, Intel, Atom, x86, ARM