I am frustrated every time I read that the iPhone doesn't allow multitasking.
Is that because according to your dictionary a microwave is a computer?
Multi-tasking is the ability to have multiple apps open simultaneously.
Do you honestly think that there's anyone who thinks the iPhone can only run one process at a time? So the iPhone can either listen for phone calls, OR check for new mail at given increments, OR keep Safari pages in memory, OR detect when you've pressed the wake button, OR monitor the proximity sensor... but none of that simultaneously?
The iPhone can not multi-task. Running multiple (background) processes, including services associated with native apps, is not multi-tasking.