im not fully convinced its api, as there are several times a dev or themselves have proved connecting to the apple service was possible. with message, beeper proved it was possible to chat with imessage users. with icloud, backups could be accessed via an internet browser (therefore theres an already existing api that is platform agnostic as it runs in a browser.)

apple could even just make a PWA and instantly have access to the same api that browsers use to access its cloud on its own, and supporting auto cloud sync wouldn’t even have to be at an OS level.