Apple iPhone 4s - Change the wallpaper

You can have multiple pages of apps in a folder.
Delete a folder. Drag out all the apps—the folder is deleted automatically.
Change the wallpaper
Wallpaper settings let you set an image or photo as wallpaper for the Lock screen or Home
screen. You can choose from dynamic and still images.
Change the wallpaper. Go to Settings > Wallpaper > Choose a New Wallpaper.