How to change your Windows 10 wallpaper
It is very easy to do it, just visit the Windows support page for detailed instructions.
How to change your iPhone wallpaper
If you own an iPhone mobile phone, please check the official Apple support help page on how to change the wallpaper on iPhone.
How to change your Android wallpaper
Android users need to check their Android version as it may be different from version to version. Newer devices, running Android 7.1 and up, can follow the steps described on the Android support page.