To use a screensaver on your iPhone, you need to enable a wallpaper image. Your iPhone already contains some still and dynamic default wallpapers. Its still images include photos and designs; the dynamic options are typically different color screens with moving bubbles. If you prefer, set your own photos as screensavers. Enable a wallpaper image or photo on your Lock screen, so it shows when your iPhone goes to standby, and on your Home screen, where it appears behind your apps.
Enable a Wallpaper on Your iPhone
Tap Settings on your Home screen and then tap Wallpaper.
Your current wallpapers display. To change these options, select Choose a New Wallpaper.
You can set images from Apple's default wallpapers or from your own photos. To browse the defaults, select Dynamic or Stills, or go to the Photos area and locate the photo you want to use as a screensaver.
When you've found the image you want, tap it to open a preview screen. If you've selected a photo, you can enable or disable Perspective Zoom. Apple introduced Perspective Zoom in iOS 7 to help users control image movements and zooming when they move their handsets or open apps. If you leave this setting on, your image may not scale exactly. If you don't want this effect, turn the setting Off, otherwise leave it On. You can always go back and switch the setting later if you change your mind.
If you're happy with the way the image looks, select Set. To choose a different image, select Cancel to return to your image files.
Choose the screen where you want the wallpaper to appear by selecting Set Lock Screen, Set Home Screen or Set Both.
Wait for the Setting Wallpaper notification to finish. The wallpaper should now show on your screen or screens. If you enabled an image on one screen and want to add another to the other screen, repeat the process.