Double click the home button...the screen will slide up revealing all the apps that are running...hold a finger on one of theses apps until they start to wiggle then you will see an X on each one which you can tap to close it.
It's actually (-) not (X) on the icons of running apps at the bottom. I know because I made the same mistake when referring to this a while ago. (X) appears on the springboard icons when you want to move them around or uninstall apps.
It's actually (-) not (X) on the icons of running apps at the bottom. I know because I made the same mistake when referring to this a while ago. (X) appears on the springboard icons when you want to move them around or uninstall apps.