Add a GIF to your iPhone Mail Signature
This tutorial is from CNET in 2010(!), and I'll summarize it here. The final result will be a home screen icon you will click to write an email that will have that GIF or JPG signature (emails written directly from the native IOS email app won't have the signature, and neither will a reply to an email sent to you).
1) The GIF or JPG you want to use must be 80KB or less.
2) Go to CoolGeex on your desktop computer and open a free account.
3) Fill out the form with the information and logo/GIF/JPG you want to be your signature.
4) Click "Create Signature at the bottom of the page to see how it will look.
5) If you like it, click "Email Signature URL" at the top left of the page under "Options".
6) Open the email with your iPhone, and click the link. A new home screen icon will appear on your iPhone. Use this new app to write an email.
That's it. Granted, it is limited.
