This is something I've been trying to get my head around when I was trying to load one of my older apps.
There's a lot of threads where people are asking for the supported audio formats in iOS. And in most of them someone comments that support for AMR (Adaptive-Multi-Rate) was dropped in iOS 4.3. How do they know this? Supported Audio file formats in iPhone
But I cannot find ANY API changes or anything about this in Apples official documentations.
i.e. the diffs between 4.2 and 4.3: https://developer.apple.com/library/ios/releasenotes/General/iOS43APIDiffs/
How can I get some actual documents saying that this actually happened?
Any help here would be much appreciated!
The closest I ever found to a document or official statement were two responses (login required) by an Apple Employee on the old Apple Developer Forums, both saying:
As of 4.3 iOS does not support encoding or decoding AMR.
If you want AMR you'll have to put in your own decoder.