Wait, when Apple started the iPhone they had no 3rd party application, people begged them to allow that. They got to that number from zero. They are not preventing anyone to create a phone so compelling that everybody is asking for a SDK. moreover hundreds of mobile allowed 3rd party apps before the iPhone was there(I remember those cheesy java apps). They sold a very expensive phone that had less feature than the others and everybody wanted one. I don't know exactly what more proof we can get than the market is free than that. It was more expensive and had less feature than the other. The only extra stuff was Steve Jobs, sorry but the marked for that was destroyed a few month ago.
Remember, when Apple started, the market basically didn't exist. Not many people had smartphones. The programs available for, say, Windows CE, had costs of $10-$20 at the low end. Feature phones had games, but they were often $5+. On a feature phone, if you replaced it with a new model you may have lost whatever you purchased.
I distinctly remember one of my Sprint feature phones having a version of Tetris (or some similar complexity of game) for $3 a month.
It was the rise of Apple's mobile app store that made apps an important factor in which phone to buy. Before the iPhone app store, what percent of users in the US spent $10 a year to buy phone apps? What percent do now?
Ignoring the fact I love my iPhone, I would be hesitant to go to another plstform because of all the games I'd have to either give up or re-buy.
It's hard to remember that when Apple started the RIM BlackBerry was the undisputed Ph.D. of the smartphone market compared to the relatively high-school smart challengers of Danger and Palm.
Palm had an app store first and it was amazing for its time. It's an interesting case study to deconstruct how they could botch such an amazing product so thoroughly. They even missed the tablet bandwagon completely.
