I've got an iPhone 6 running the latest iOS 9.2.1 public beta, although the following behavior has been happening to me for a few iOS updates now. I'm wondering if it's a beta bug that should be reported or if it's the intended iOS behavior.
When I'm using headphones, everything works the way it should, regardless of the ringer switch setting.
When I'm not using headphones and the ringer switch is set to on (i.e. the orange isn't visible), everything works the way it should.
When I'm not using headphones and the ringer switch is set to off, audio from video-playing apps (YouTube, the native Videos app, etc.) works fine, but the audio from games is totally silent.
So, is this a bug or a feature? Let's define "feature" as "it can be reproduced on a device that has never touched beta software."
Best Answer
This is intended behaviour as per Apple Guidelines.
From the Apple iOS Human Interface Guidelines:
Specifically for games:
Deeper in the Audio Guidelines per App Type, Apple recommends use of the AVAudioSessionCategoryAmbient or AVAudioSessionCategorySoloAmbient categories, which are defined as:
Accordingly, for playback type apps, the recommended category is AVAudioSessionCategoryPlayback, defined as such:
As long as the developers follow the guidelines, this is the expected behaviour unless Apple decides to change how the categories function in the operating system.