FAQ: Why does Loopy keep running in the background? How do I stop it?
Loopy is designed to work well in a multitasking audio environment, so you can use it in conjunction with other apps, such as drum machines. Once Audiobus is released, this will be even more important.
Loopy by default will remain active in the background for this purpose, rather than shutting down when you switch to another app. This approach is becoming more common, as more apps become multitasking-friendly.
If you don't want this, then open Loopy's settings, and turn off "Play in Background".
Alternatively, you can quit any app at any time by clicking the Home button once, to go to the home screen, then double-clicking the Home button again to open the multitasking menu. Then, in the multitasking menu, hold your finger on the app you wish to close until the "-" buttons appear at the corner. Tap the "-" button to quit the app.