To set a live wallpaper on your iPhone, you first have to:
- Go to Settings
- Select Wallpaper
- Tap Choose a New Wallpaper
- On the right-hand side, select Live
- Now, you can choose from the default live wallpapers available.
If you want to make your own live wallpaper using an image you already have, then scroll down to the Live Photos album and select a live image from there.
If there is a video on your camera roll you want to use as a live wallpaper, you need a third-party app to do so. intoLive is one such app that allows you to pick any video you’ve taken and edit it down to a live wallpaper format up to 5 seconds long. Once you have selected and edited the video, you can choose it inside Settings and use it as your new live wallpaper.