No App Store
Since the iPhone had such a great web browser, Apple’s original strategy for the iPhone was to rely on web apps, so with the first iPhone there was no legitimate way to install third-party apps at all, not could you even rearrange the home screen. What you saw was what you got.
Of course, web apps never really took off, for fairly obvious reasons, and by the following year, Apple had relented and debuted the App Store with a big splash in iPhone Software 2.0 (it wasn’t called “iOS” until 2010) and the iPhone 3G. Of course, the original iPhone could also benefit from the App Store by installing the latest software update.