If you can use a real domain and real SMTP server for your meteor project, it will also look more trustable. Also many people don’t even have their email clients setup… I incidentally do, although I don’t use it at all, but I know many people, who don’t use that anyway, so I question, whether it would even work out well for you. Also, you could ask your user for email address and send the email with their email address as sender, however some webhosting providers don’t support this, because it can be misused for sending spam, also many spam filters will move such messages directly to spam folder.