With its multi-tasking, it's easy to launch lots of applications on Android. I understand that background applications use fairly minimal resources, but they often activate features (GPS WiFi etc.) that drain the battery. How can you find out what applications are running and what resources they're using? and how can you stop them safely?

I tend to rely on Recent Apps list to bounce between apps I use most often, as a sort of day-long history, for example. Is there a trick to increasing how many apps are listed in the default Recent Apps list (long-press home > Recent Apps)? I believe it's limited to 8, is there a trick/app which would increase it? Picture the PC Alt-Tab menu when you have 10+ programs open. Perhaps it makes more sense on a phone (from …

What are the main differences between Android and iPhone implementations of multitasking at the application level? (Let's not turn this into a subjective fanboy argument please?)