The iPhone has never prevented you from running your own code on it. It shipped with a javascript SDK and then within the year they opened it up to objective-c

The iPhone has never prevented you from running your own code on it. It shipped with a javascript SDK and then within the year they opened it up to objective-c programs. They charge you $99 a year for the certificate signing service, but it's really no big deal... if you can afford an iPhone you can afford $99 a year. (Hell, I think these days you don't even need to be a paid developer, the free developers can run their code on their phones.)