Music Player (no-ads): Add Exit button in App

Components

Music Player (no-ads) is a music player on android devices. It is free, light weight, basic, offers no ads and is a good music player in many ways. But it does not have an exit button to close the app totally when it's not being used.

Proposal

I'm suggesting that an exit button be added to the app to enable users close it totally when they're done using the app to play music and this feature should as well disable the app from running in background on the device.

Mockups / Examples

Benefits

Adding an exit button to the app will enable users to close the music player entirely when not it use. This will stop it from running in the background and save memory which will enhance device overall performance.
Presently the only option is to minimize it and when this is done the app keeps running in the background even when the user is no longer playing music.