A free program for Android, by Xzerow.

DJ Marshemello Mp3 Offline is a free application for Android users to listen to their favorite music. The app is designed with HTML and CSS, so you can listen to music offline without having to spend data on the internet. This is very convenient for people who have a poor internet connection or a mobile phone that has a low data capacity. You will not have to worry about not being able to listen to your favorite music. You can listen to your favorite music even when you’re offline. The app is designed to be fast and lightweight, so you won’t have to worry about the application slowing down your phone.