Something I discovered recently that bears writing down: you can define all the handlers and actions you want in your code but if you don't actually list them in your android manifest, then you can't dispatch intents to them.

I had written the main Action of the chicken book to list all the entries and that worked, and I'd made a second Action to display and edit a single entry and that worked. Then, since it was perfect, I fixed it and in the fixing I removed the reference to the single entry Action from the android manifest. My logic was, "I'm not going to launch directly into that screen, so why should I need to provide an entry?" Well, the logic was flawed; apparently when you dispatch an Intent to an Action, even if you specify the class directly instead of letting Android do the filtering and late-binding, Android still requires the target Action to be registered in a manifest somewhere. Without that, the application quits unexpectedly.

This makes me wonder if the problem I had with the corporate email app wasn't a somehow-corrupted android manifest.