Recalling that aha! moment, Forstall explained: "I'll never forget we took that tablet and built a small scrolling list. On the tablet, we were doing pinch and zoom. So we built a small list to scroll on contacts and then you could tap on it to call. We realized that a touchscreen that was the size that would fit in your pocket would be perfect for the phone."
And so, in late 2004, the idea to create a uniquely Apple smartphone was born.
As work on the tablet project stopped, Apple began dedicating resources towards creating a phone, a daunting task for a company with no previous significant experience in the cellphone industry, save for the flop that was the Motorola ROKR.
But as Schiller explained at trial, Apple saw a lackluster market it could really deliver some innovation to. "At the time, cellphones weren't any good as entertainment devices," Schiller said.
And with the iTunes Store already a runaway success at that point, Apple knew a thing or two about delivering media content to portable devices.
Project Purple: Creating iOS
A 15-year Apple veteran, Forstall's history with Steve Jobs goes all the way back to 1992 when Forstall, then a recent Stanford graduate, began working at NeXT - the company Jobs founded after his unceremonious exit from Apple in the mid-1980s.
Forstall soon became one of Jobs' most trusted lieutenants, having played integral roles in the development of various iterations of OS X. It's therefore not surprising that Forstall was the one tapped by Jobs to create the software that would power Apple's revolutionary device.
Jobs gave Forstall free rein to handle development of what would later be known as iOS, albeit with one constraint - Jobs told Forstall was that he was not allowed to hire anybody from outside the company. Instead, Forstall was free to choose anyone he wanted from within Apple to join the nascent iPhone team.
With that directive in tow, Forstall scoured the ranks at Apple and honed in on the company's best and brightest engineers as potential additions to the team.
But due to the secretive nature of the project, Forstall wasn't even able to tell potential iPhone team members what Apple was working on or even who they might be working under. Instead, potential team members were given a rather cryptic offer.
Forstall told them that Apple was working on something great and that if they chose to join the team they'd have to "work hard, give up nights, work weekends for years."
Before long, Forstall had assembled a core team to work on the iPhone's software and it was time to get to business.
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