Sometimes plain-text in an email won’t do. In those cases, you might want to add a little bit more expression using rich text. With this form of text, you can use bold, italics, and underlines in your email body or just the signature. Here’s how to do it.
Although Mail on iOS can display rich HTML email messages, you can’t do much more than add bold, italics, and underlines to message text.
There is, however, a way to enhance your signature with rich HTML formatting. You can use any app that can create rich HTML text, but probably the easiest way to do this is to use the rich text signature from the email app on your Mac or Windows PC.
Your new signature is included in any email messages from that email account. As a bonus, if your signature consists of an email address or phone number, you’ll be able to send an email to that address or dial that number by merely tapping it.