ALAC is open source and you can feel free to contribute to it or "adopt"/use it.Apple has been using ALAC for a long time on difference devices and platform. Moreover, according to Wikipedia, "compared to some other formats, it is not as difficult to decode, making it practical for a limited-power device, such as older iOS devices". "Adoption" is not a reason, from my point of view, ask a company/app abandon an open sourced format to use another one.