The App Switcher, one of the most frequently used feature on iOS 7, can be accessed by double pressing the Home button. If you ever wanted to access the App Switcher from Control Center, you might want to check out a new jailbreak tweak known as CSwitcher.
Developed by Brogan Miner, CSwitcher replaces the Quick Launch apps in Control Center with the App Switcher, allowing you to take a quick glance at the apps running in the background directly from Control Center as well as close any of them. Personally, since I never use the Quick Launch apps, CSwitcher could be a good replacement.