xcode - For the iPad or iPhone, how do you control the system Volume? For example, have a button that mutes all audio -

I would like to create a button in my iPad app (probably will be similar to the iPhone app) when I push this button, All audio is mute, even if you exit the app

I do not see it anyway that you can control the volume, although I'm sure there are other apps that I have installed on the iPhone App Store Have seen in I have also read that some places doing so may have rejected you from the app store.

How can I reduce or decrease the iPad amount from an app that works even when the app is closed?

Thank you!

AFAIK, you can not, at least not programmatically. But you can integrate an MPVolumeView.