The reason you see open source there at all is because we came in and said there should be a platform that's identical with millions and millions of machines.
You may choose to include some music, if you think/know, that the receiver is able to play it.
Put receiver's email address in the first field. You may supply more than one email address, as long as you separate them by comma. Put your own email address in the second field, eventually type a message to the person, and click "Send".