From Playdate Community Wiki
Description from itch.io page:
I put together a little music file browser to enable me to audition music and sound effects on the device, to make sure the volume levels and looping was correct. Some time later I added support for animations (Animated .GIF or .PDT image tables) and static images (.PNG or .PDI).
Since then this little app has taken on a life of its own and is being used as a portable music player. I may have accidentally reinvented the iPod!