How do ya close an application?

It doesn't matter if something is running in the background; if you go back it will be up to date. That's multi-tasking and the iPhone doesn't do that well

Try pressing the menu button (left soft key) and see if an exit button pops up in the context menu (some apps don't). Otherwise you can just hit the back key (right soft key) until back at the main screen. Android will close apps as they interfere with performance. Some apps still collect data in the background even if they are turned off. If you don't want that drain on your data plan, go to settings | accounts and sync then uncheck auto-sync.