As another poster stated, Apple are kind of design fascists. Phones, they decided for me, are just too small to support many of the multitouch gestures that the iPad uses. Jailbreak and you can have that (very useful, IMHO) functionality back. The quick access buttons are the ones they decide you need. Jailbreak and you can choose from a huge set of functions that, again, are really handy to be able to toggle quickly. I was turning certain device features (BT, hotspot, invert, etc) on and off frequently enough that creating buttons for them made a huge difference in user experience.
Many of those features would be trivial for Apple to implement as advanced settings (hell, solitary coders are writing this stuff and giving it away for free), and not against the Apple ethos (unlike, say, emulators). But for now you have to expose yourself to security risks in order to do all this useful stuff with your expensive pocket computer.
And Android is its own bag of cats. I've been in that bag with those cats and it's a longer story that I have time to write about here. Suffice it to say that not everything in the Adroidverse as universally open and moddable as it might appear from the iSide.