If you want to quickly call, FaceTime, or text a contact, there's no need to open any of the related apps. Those who have iOS 8 on their iPhone can quickly access Favorite and Recent contacts via the App Switcher.
Double press the home button. Above the App Switcher you'll see a swipeable menu of contacts. Swipe left to see Recent contacts. Swipe right to see Favorites.
Tap on a contact and you'll be given the option to call, text, or FaceTime the person.
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