Multitasking explained
I will suggest, however, that my home computer has a big enough screen to accomodate more than one app going at the same time at once so I can MULTI-TASK.
The bottom line is, the ONLY advantage the Pre has in this department is saving the SECONDS it takes to load an app in to memory.
Multitasking have very little to do with either A) viewing multiple programs on the same screen or B) saving time between loading apps (although would this would be nice to avoid on some apps). It also has little to do with background processes. By "desktop-class" multitasking, I believe he means adapting that which makes multi-tasking such a fundamental part of the desktop experience to a mobile device. I'll first consider your points:
A) Multitasking is not about seeing multiple apps simultaneously on the screen. I'll assume that you will reply that, in fact, you do have all your running programs in small, adjacent, concurrently-viewable windows at all times, because it has very little to do with my point. That isn't how desktop UI is designed. If it was, windows would automatically divide your screen into four windows if you had four programs open, and a 2x3 grid if you had six open, etc.
Instead, programs generally open in full screen (maximized) windows. All your attention is focused on this program. At the bottom is the taskbar, where each running program occupies a space and can be easily maximized to shift your attention to that program. Regardless of how one personally uses the windows, our attention can only be focused at one point (and program) at a time. For example, you may be viewing two windows: reading from one and entering data into the other. Your attention is still focused in one program at a time (reading, then typing); you are simply making it quicker to transfer information from one into the other. When you are running multiple programs you have multiple tasks on the taskbar, ergo, you are multitasking.
Now, a mobile device is too small to make effective use of a taskbar since it would be too small to see all your tasks at all times. The Pre adapts the idea with the card system. You zoom-out to see all your tasks, then you zoom-in on a particular app to bring it to your attention.
B) Multitasking is not about being able to save time loading programs. My desktop can launch any program faster than my iPhone can launch it's apps. If load times are the issue, however, why aren't desktops designed to run only one program at a time? In fact, why even bother with multi-core processors which truly shine with multi-tasking? The fact is it is better to be able to run multiple programs. When we can't, it's due to some limitation.
Limitation implies something that would be done, if it could be, but it can't - not that it would be bad or useless to do.
Multitasking is about organizing workflow.
The whole success of mulitasking is keeping context in an organized workflow. Although you may shift your attention between programs, your train of thought is preserved. Many times while doing one thing, a thought will pop into our heads (example: "Oh, I gotta do
this-n-that!"). If you don't act on it, you will continue what you were doing uninterrupted but you are unlikely to be able to recall what it was later. If you do act on it, your thought process will shift and you will switch to whatever program is required to complete the thought. When you are done, your brain will stall while you try to get back on the original thought process you were at. You can switch back to your previous task, of course, and your brain will snap back right to where it was. If you are left back at the desktop (or home screen), however, you'll have no such mental cue and your train of thought has to get rolling again. It may not be hard or time-consuming to remember what you were previously doing and get back to where you were, but that's how our brains work.
Why do you think tabbed browsing caught on so effectively? It's a perfect example. You may be reading a thread on macrumors and see something interesting that you want to research. What do you do? Open a new tab, of course, and start googling! You may browse a lot of pages as your train of thought explores that idea to exhaustion. When you are ready to get back to the topic, however, you switch tabs and BAM! you are right back to the thread. Now you have two tabs, one is your browsing over the forums and the other is a tangent into some other subject. More than just browsing history, they both equally represent and organize two separate trains of thought.
I'm sure you'll say that it's not a big deal. Why don't you try using your desktop like you have to use the iPhone and see how long it lasts. Close your current program before opening another. It must be completely closed and not running in the background (like IM programs that can receive IM's in the background even without any GUI windows). Listening to music is an exception unless you need to bring up iTunes to do anything other than previous/pause/skip. Multiple browser tabs are allowed as long as you refresh the page as you return to each tab.
Apple understands multitasking but had to compromise.
Apple understands multitasking! This is evident by the way they designed their apps to keep context when leaving the app. Their compromise was that since apps can't stay open, they'll just have them open to the same screen from when they were closed.
This system mimics the behavior you'd see with multitasking. Good start, but it has some limitations. First, and not least of which, 3rd party apps have their own behavior and often don't do that. I'm sure you will respond that it is a problem with the developers, but guess what? Users have to live with the apps that are available. For example, here is my home screen:
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Bloomberg:Always launches into the headlines and downloads new content, despite any article I may have been in.
Mobile Pro: logs me out! (most notably disables streaming quotes and trading)
USA Today: Same as Bloomberg.
iStat: always starts at first screen.
Pandora: do I really need to say?
Omnifocus: long load times. The real kick in the teeth is that this app would have almost zero processor load when multitasked.
You may say they are poorly developed apps, but what am I supposed to do about it? Second, this system does nothing for apps that actually have some processing to do while not in the foreground. Finally, apps themselves will often shift the focus by launching another app. When you close that app, however, it does not return you to what you were originally doing. Imagine if any link you opened in a new tab closed your current tab.
The iPhone does not multitask.
The iPhone is not multitasking when the iPod is playing in the background. That is a background process - just like every other example people give for the iPhone multitasking, be it mail, safari, phone, etc. There is no interaction, no workflow, no thought processes associated with bringing attention to these apps.
The one instance of true multitasking on the iPhone is the feature that brings up the iPod controls with a double-click of the home button. You should consider how often you use this feature and how useful it is to you. To me, its probably one of the most useful features on the phone. I find it extremely handy that while I am doing
anything on the device I can bring up simple controls for music playback (especially stopping it) withing interrupting what I was doing.
Imagine if Apple implemented the same system with text message pop-ups. Instead of limited to closing the alert or launching the messaging app, what if there was a field to type your reply to be sent in the background while you continued whatever you were doing.
That would be multitasking. I would also wager that, when implemented (yes, 'when'), people are going to go nuts about it.
Even if Apple implemented a multitasking system where minimized apps were merely a
screenshot and it didn't actually run at all, it would be an improvement. That would be assuming of course that it would load again to the screen you were at.
More examples of how multitasking would benefit the iPhone
In general, true multitasking that is so effective in keeping context and organizing workflow and thought processes is the best (and subtle) benefit: Replying to text messages while browsing the web, writing an email and checking your calender, identifying a song with shazam while reading macrumors, etc. However, there are plenty of situations where it's just flat out necessary, for example:
An app using the GPS to track a run, Nike+, or an app for the
BodyBug.
Transferring files to the iPhone with the various file sharing apps.
Turn-by-Turn navigation.
Streaming media.
All of these apps run would need to run continuously to do what they were designed to do. That is generally true for any app in the app store that disables or circumvents the auto-screen lock as it would interrupt their function. While using them, forget about doing anything else - except advancing tracks on your
current playlist/album.
