Video containers don’t determine codec. You can use any video codec as well as any audio codec. Which means the audio inside an mp4 can be mp3, or flac, or aac, or wav…
If you’re just storing audio, just use an audio file directly. Putting the same exact audio stream inside a video container just makes it slightly more difficult to play, because them you can’t use a lot of audio players to play the audio.
Why yes, video containers typically support audio tracks.
And you could encode such files with only an audio track.
But why would you?
Better audio compression codec than the mp3 standard?
Video containers don’t determine codec. You can use any video codec as well as any audio codec. Which means the audio inside an mp4 can be mp3, or flac, or aac, or wav…
If you’re just storing audio, just use an audio file directly. Putting the same exact audio stream inside a video container just makes it slightly more difficult to play, because them you can’t use a lot of audio players to play the audio.
I dunno, ask Apple. I just said it can be done, not that I actively do so
It’s a video container. If apple is using it for audio only, that’s like using a pickup truck to transport two bags of groceries.
Of course it’s “possible”.