I am developing an app on iphone that lets user take photos, add comments & GPS location to it and send it as an email to another user.
If the recipient has installed the same app & when she clicks on the attachment the same app will launch & parse these details & show them to the recipient. (I intend to use UIDocumentInteractionController for some of the stuff here)
Problem: whats the best way to encode this data in a single file & then retrive it upon arrival from the email.
This is pretty high level, but here are the general steps:
First, register your own file type as described here.
Then, archive your data using NSKeyedArchiver.
Next, attach it to an email using MFMailComposeViewController. Make sure you give it a filename that matches the file type you registered earlier.
Finally, implement application:didFinishLaunchingWithOptions: to handle the case when a user tries to open your email attachment. (Currently, it's the fourth bullet in the method documentation.)