Here is a simple and easy way to use your own video as your phone/tablet's wallpaper.
Here's how you can do it.
Touch and hold the home screen till the pop-up to change your wallpaper comes.
Then choose the video wallpaper option from it.
You will see three options in the video wallpaper section - Default, SD card, and Camera.
If you want to use the pre-installed video, select Default. If you have already a video, then choose the SD card option, else choose camera to shoot a fresh video and use it as a wallpaper. Once done, click the "Set Wallpaper" option to change the wallpaper.
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