A while ago, Ole Begemanne discovered that the MFMailComposeViewController was not built and presented inside of your application anymore, but rather was a ‘RemoteViewController’ presented using XPC from Mail.app. With it has come a lot of speculation about if & when Apple will start to allow us to use XPC to interact between apps, either in the form of RemoteViewControllers or offloading specialized work to processes presented by other apps.

I wanted to think about how this may work from an interface perspective.. specifically whether we would need to distribute headers / SDKs to developers for them to utilize our RemoteViewControllers, or if they could use them more generically. Here are some explorations around how they could be presented to developers.. it’d be great to see other people’s thoughts on this too..!