Register UTI Document Type in iOS7

I want to be able to import content in a zip (json, images, etc) and so that double-clicking on the file in an email attachment associates the file with my program, I want to change the .zip extension to (for argument's sake) .ziptest

I've added the following to info.plist but double clicking on the attachment in the mail program doesn't offer my programme as an option, any hints?

  <key>UTExportedTypeDeclarations</key>
  <array>
    <dict>
      <key>UTTypeDescription</key>
      <string>Zip Test</string>
      <key>UTTypeConformsTo</key>
      <array>
        <string>public.data</string>
      </array>
      <key>UTTypeIdentifier</key>
      <string>com.myurl.ziptest</string>
      <key>UTTypeTagSpecification</key>
      <dict>
        <key>public.filename-extension</key>
        <string>ziptest</string>
        <key>public.mime-type</key>
        <string>application/zip</string>
      </dict>
    </dict>
  </array>