[ZitchDog]

2) you can manually close apps. Long-press on them in the multitask bar and click the "x" to close. Next time you go in you will get a clean slate.

3) iOS will shut down LRU'd apps as it runs out of memory. This is a non-issue.

Most of the issues for me around multitasking center around the UI.

[Stormbringer]

(2) You shouldn't have to manage them manually. Also, but orthogonal to that is that the multitask bar blows from a user experience point of view. (Just by way of example, if you do decide that the user should manage memory manually, you should at the very least provide some kind of indication about how much memory/threads/resources each app is currently using, otherwise the user is just shooting blanks in the dark (sic)). You didn't previously (need to do this) under single tasking. For most apps therefore single tasking provided a superior user experience.

The obvious exception is apps that do some kind of notification, e.g. if you wanted to write your own SMS or twitter style client. Given the vast numbers of apps coded for the single tasking paradigm, it would have been better to create some kind of 'opt-in' notification API (a good one, not whatever they had previously).

(3) to an experienced eye the performance degrades as it reaches those limits and starts having to do app level garbage collection. Also, this means that apps need to pay more attention to their own memory management and the low-memory messages they are receiving from the OS. In a perfect world this would have already happened. Given the ... how shall I put it ... journeyman level of experience of most iOS developers this is an utterly unrealistic expectation. This is a big issue.