Why is IPhone successful?

For the same reason the PC of the 90s was. Thousands of applications written by developers with specific domain knowledge. Microsoft opened their API and a flood of applications pushed the PC to huge volumes. Apple was pushing the Mac at the time and wanted to retain control and thus did not facilitate outside development without some sort of licensing. This was the difference in the 90s. A parallel situation is happening again with the iPhone. Apple has opened development of iPhone / iPod application to the development horde and is benefiting from it. Don't misunderstand... You can make mucho dinero selling a proprietary charger and accessories to a captive audience. The difference is this, Apple has fallen back to making sure they control the hardware. They realized that software by it's digital nature want's to be open, low cost, and democratic. This is why I find no surprise that they let Spotify coexist with iTunes. It's about using software to sell the hardware. This strategy is paying off in spades; congratulations Mr. Jobs for learning from past experiences. Based on this my question to you is, is the iPhone hardware the razor or the razor blades?