Dave Lee and the BBC provide a look back at the original iPhone from a very Tony Fadell — former head of iPod at Apple and Nest at Google — perspective.

Indeed, one early iPhone concept design used the iPod's distinctive click-wheel as its input method. That was soon ditched.

"We were turning it into a rotary phone from the sixties," Fadell remembered. "We were like, 'This doesn't work! It's too hard to use'."

It just so happened that in another part of Apple, work had started on a touchscreen Macintosh computer.

There were two branches of Purple Experience Project (Purple or PEP). Fadell and team were working on P1, a more conservative prototype, while Scott Forstall and team were working on P2, what became the iPhone. If P2 couldn't get to market faster enough, P1 could. But P2 actually beat P1 to milestones like functioning SMS, and given all its other advantages, P1 ultimately went nowhere.

Listen to our interview with Nitin Ganatra on building the original iPhone

"[The fight over a physical keyboard] raged on for around four months," Fadell said. "It was a very ugly situation." Jobs, who had his heart set on a touchscreen, became so incensed with people disagreeing with his ideas that he enforced a blunt policy.

"Until you can agree with us you can't come back in this room,"" Fadell recalled Jobs saying to pro-keyboarders. "If you don't want to be on the team, don't be on the team." The disagreements soon stopped.

There was also a discussion about whether iPhone should use WebKit — Apple's HTML, CSS, and JavaScript renderer — as it's interface layer, AppKit — the existing frameworks for Mac apps — or something new. Something new won and ultimately became UIKit.

Some of the people who left Apple shortly thereafter ended up at Palm where they shipped the Pre running webOS which, wait for it, had a physical keyboard and used WebKit for the interface layer.

Also included, Fadell losing a prototype iPhone on a plane, research notes while getting lunch, and a weird story about "making iPhone work with a stylus".

Read the history of the original iPhone