Reports earlier this month suggested Apple's iPhone OS 4.0 would support multitasking. Now, the same source, AppleInsider, is expanding on its previous report with rumors that the supported multitasking will be resemble the Expose function in the Mac OS.
According to "people familiar with Apple's plans for the new firmware," a keystroke combination -- hitting the Home button twice -- will bring up the icons of currently running apps, allowing users to quickly choose the one they want to switch to. AppleInsider notes that this sounds more like the basic "Command + Tab" app switcher (similar to Microsoft Window's "Ctrl + Tab" option) than Expose, which scales all open windows down to tiny little versions of themselves, but their sources insist that the new iPhone multitasking will exhibit "several characteristics of the Expose brand."
Multitasking, or its absence, has long been an issue for iPhone -- and now, iPad -- users. AppleInsider points out that Apple's iPhone OS 3.X actually has no issues with multitasking; a number of bundled iPhone apps, including the phone and the iPod functions, are perfectly capable of running in the background while the user performs other tasks. It's third-party app multitasking that isn't supported. Currently, users must quit any third-party app they are using in order to run another third-party app.
Apple addressed the multitasking issue (sort of) in its iPhone OS 3.0 update, when it introduced push notifications. Push notifications notify users of changes in third-party apps (e-mail, instant messages, and so on), so that users can switch over to that app if necessary. Push notifications are implemented in two ways -- pop-up windows that appear on screen and give you the option of immediately switching over to that app, and as little number badges on the corners of third-party app icons (on the Home screen), so you know how many missed messages/e-mails/Scramble challenges you have waiting for you.
Currently, multiple smartphone operating systems support multitasking -- including Palm's WebOS, Google's Android OS, RIM's BlackberryOS, and Windows Mobile (though the new Windows Phone 7 series will reportedly not support multitasking) -- so Apple is a bit behind.
This is all just speculation, though, so I wouldn't hold my breath -- after all, multitasking capabilities were predicted for the iPhone OS 3.0 update, and those didn't come through.