Phillip Gruneich had a few good finds. Looks like Hog Bay’s excellent PlainText has added x-callback-url support.
Also, though undocumented by Google, it has apparently made it’s way into the Google Maps app.
Sebastian Rehnby has published SBRXCallbackURLKit on Github. SBRXCallbackURLKit is a “simple library that makes it easy to add x-callback-url support to your app.”
SBRXCallbackURLKit has a block-based API for declaring URL handlers and Cocoapods support for easy integration. Worth a look if you are getting started on URL scheme integration in an app. You might also want to look at Inter-app Communication, which works in a similar fashion, and see which best suits your needs.
Lots of great new things happening with Tumblr for iOS lately. Including the addition of some great x-callback-url support!.
Nice overview of activity in URL schemes development on iOS – with pointers to some great projects to make it easier to implement URLs in your own apps.
AppCubby’s excellent app Launch Center Pro has updated to version 1.1, now with excellent x-callback-url support. Still waiting on official docs on all the possibilities, but Federico Viticci will get you started on some of them at MacStories.
Inter-App Communication, IAC from now on, is a framework that allows your iOS app to communicate, very easily, with other iOS apps installed in the device that supports the x-callback-url protocol. With IAC you can also add an x-callback-url API to your app in a very easy and intuitive way.
Looks very cool. Been thinking about implementing x-callback-url, but haven’t? You might want to check out this library.
Great article about some of the things you can accomplish with x-callback-url support.