With the introduction of the iPad a new discussion has arisen. The need for multi-tasking. And of course the fact that the iPad lacks this ability. At least, that is what the iPad opponents (what’s the use of being against a handheld device, I wonder?) keep repeating (along with the non-Flash argument of course).
At first I went along with the multitasking argument. How can this device be useful if you cannot play music while checking your email? Because I am sure that is exactly what I would use the iPad for. And then it dawned to me. What do we mean with ‘multi-tasking’ anyway?
Our friend Wikipedia provides an interesting definition: In computing, multitasking is a method by which multiple tasks, also known as processes, share common processing resources such as a CPU. In the case of a computer with a single CPU, only one task is said to be running at any point in time, meaning that the CPU is actively executing instructions for that task. Multitasking solves the problem by scheduling which task may be the one running at any given time, and when another waiting task gets a turn.
So, what does this definition imply? Multitasking means that multiple processes share the same CPU, and parts of those process are in fact running seriated. By means of a context switch the processes are reassigned to the CPU. When the frequency of context switches is high enough, the illusion of parallelism is achieved. Of course, with multiple CPU’s or CPU cores, true parallelism is possible.
With this information in mind, let ‘s go back to the iPad (or iPhone, which has basically the same OS). The iPad OS is, if we may believe various sources on the internet, capable of running background processes, in any case for the built in software. If that is the case, nothing stands in your way to listen to your favourite album while typing an email. At the same time! Well, perhaps with some context switching, but you won’t be bothered by that at all.
Leaves us one other question. What is multitasking from the end users point of view? I think most users will come up with the vision of having dozens applications on their desktop, where they reside next to each other and the user is constantly switching between programs and making them interact in many ways.
… in fact, most applications seldom interact with each other, at the most in the case of copying information from one to another. Be honest, that describes most of your in-between application activities when working on your desktop OS. And any decent user interface should be able to copy and paste data between applications. Yes, that includes the iPhone.
Don’t forget that the average user is not so capable of multitasking himself. Try doing any number of tasks simultaneously and you’ll find yourself switch-tasking in no time. And that is usually the least effective way of getting things done, because we are not as capable of switch-tasking as the average CPU.
So, wrapping this up, I’ve come to the conclusion that the limited ability of using multiple applications simultaneously is not the big disadvantage some people want us to believe. Even more if you keep in mind where the iPad is meant for: the more casual work and entertainment, as so to say.