I can't count how many times I've sat back and debated with people who call the iPhone a smartphone. For all of its gloss and glamour, its SDK, its connectivity, it's no smartphone at all for one big reason and one big reason only. Any modern smartphone should present itself as a viable desktop alternative. Any good desktop computer features multitasking. The iPhone can't run third party application in parallel, forcing users to run apps in series, with no background processing.

Why Apple allows its native applications to run simultaneously, but not its third party apps is a mystery left to Steve Jobs. How to implement multitasking on your iPhone on your own isn't such a mystery, though. Thanks to the skillful work of gaizin, part of the well-known iPhone pwning community and software utility developer, Jobs' minions can now run multithreaded third party applications. Requiring you first jailbreak the device, or remove the default security layer, the hack allows you to run apps simultaneously, and set rules for which apps run in the background by default.
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