iPads, and iPhones, refuse to run programs unless they're authorised by Apple. Here's what Cory Doctorow says about this and about other devices that have similar restrictions:
"Today we have marketing departments who say things like: 'We don't need computers, we need appliances. Make me a computer that doesn't run every program, just a program that does this specialized task, like streaming audio, or routing packets, or playing Xbox games, and make sure it doesn't run programs that I haven't authorized that might undermine our profits.'
And on the surface, this seems like a reasonable idea —- just a program that does one specialized task —- after all, we can put an electric motor in a blender, and we can install a motor in a dishwasher, and we don't worry if it's still possible to run a dishwashing program in a blender.
But that's not what we do when we turn a computer into an appliance.
We're not making a computer that runs only the 'appliance' app; we're making a computer that can run every program, but which uses some combination of rootkits, spyware, and code-signing to prevent the user from knowing which processes are running, from installing her own software, and from terminating processes that she doesn't want.
In other words, an appliance is not a stripped-down computer —- it is a fully functional computer with spyware on it out of the box. Because we don't know how to build the general purpose computer that is capable of running any program we can compile except for some program that we don't like, or that we prohibit by law, or that loses us money. The closest approximation that we have to this is a computer with spyware — a computer on which remote parties set policies without the computer user's knowledge, over the objection of the computer's owner."
Cory Doctorow, "The Coming War on General-Purpose Computing", http://boingboing.net/2011/12/27/the-coming-war-on-general-purp.html. See also transcript by Joshua Wise at https://github.com/jwise/28c3-doctorow/blob/master/transcript.md —- Watch or read the whole talk. It starts slowly, but rapidly gets very smart.
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