I suspect @cag might be asking if there would be an api to tie in with the Obsidian sync service, so you could add notes directly to your Obsidian cloud from anywhere.
I think in the general case it would probably be better to use a third party sync service if that’s a concern though. Even if there was an api for it, there is more likely going to be third party support for Dropbox or Google drive than Obsidian