iPhone Signature with Image
If you do not want only text in your signature, you can also use an image as your signature on your iPhone. It is impossible to do this without using a third party app.
Use Safari on your iPhone and navigate to http://www.coolgeex.com/iPhoneSign/.
Fill out the form, such as your name, email address, phone number and address. Some of the information is optional, but the form requires you to enter your email address. The title and company have options to use any font color, and either bold or italic type.
Click the Choose File button under Upload Logo if you want to insert a picture. Smaller pictures works best as you cannot resize the picture after it is uploaded.
There are checkboxes beneath the logo that you can check to add or not add items, such as email address, WEB URL or Facebook icons. These items do not show as a default. If you want them to show, you must check the appropriate checkbox.
Select a PIN number and enter it into the appropriate field. You need this number to use your signature for the first time. Click the Create Signature button when finished.
A link appears on the next screen that opens. Use your iPhone’s browser and navigate to the link to retrieve the signature.
When you reach the site, you will be prompted for the PIN number you just created. When you enter in the PIN number, a blank email message opens displaying your custom signature.
Select the signature and copy it to save it. Tap Settings from the iPhone home screen, tap Mail, Contacts, Calendars, and then tap Signatures. Paste the signature into the settings.