iOS inter-app communication

We have an iOS app that contains a series of contexts such as text pages and video segments. We want another app to be able to request the display of a specific context.
In researching this issue, I cam across iOS’s Custom URL Schemes. Is this a good mechanism for the communication? What would be the best method of implementing this in a Unity app?

I guess you already solved your issue. AFAIK this is the only available way to communicate and send instructions “directly” between apps on iOS in the same device.

If you were to pass parameters you can simply agree on custom url and parameters between the apps and parse them inside application:openURL:sourceApplication:annotation: delegate call. then based on that you can call UnitySendMessage method from the native side to your gameobject method with your instructions.

reference:
http://developer.apple.com/library/ios/#documentation/uikit/reference/UIApplicationDelegate_Protocol/Reference/Reference.html