According to Apple Inc.: These are the officially supported iOS 7 devices:

iPhone 4
iPhone 4S
iPhone 5
iPad 2
iPad 3
iPad 4
iPad Mini
iPod touch 5th gen

Filters in Photos app – iPhone 4 and newer, iPad 3 and newer
Square photos and video formats – iPhone 4, 4S, 5, iPad 3, 4, iPad mini, iPod touch 5G AirDrop – iPhone 5, iPad 4, iPad mini, iPod touch 5th gen

Live filters from Camera app – iPhone 5, iPod touch 5th gen
Swipe & Panorama Photos – iPhone 4S, iPhone 5, iPod touch 5th gen
iTunes Radio – All iOS 7 devices will get iTunes Radio through the Music app