Making Google Calendar and Gmail the "Default Applications" for calendar and mail

Solution 1:

1) It is the "MimeType" line in the Desktop file, containing "x-scheme-handler/mailto;" which causes the application to show up as a preferred email handler.

The Preferred Applications "Default Applications" capability is fairly well hidden in GNOME 3, as the "Default Applications" tab in the "System Info" utility.

Consider using the GNOME Gmail package. It will take care of this for you, integrating your default browser as the desktop (Gmail) mail handler. It does not handle the calendar link - that would require an additional Desktop file.

4) You won't find better mailto URL handling for Gmail than GNOME Gmail (http://gnome-gmail.sf.net). It will properly work with Naultilus "Send To...", and even supports Libre Office 'Send -> Document as Email...".

Solution 2:

You can install Gnome Gmail on Ubuntu Unity using the Ubuntu Software Centre Application.

Once installed, just run Gnome Gmail and check the box that says to use it as the default mail application.

Super simple :D