There are several reasons that leads to the query related to how to add logo to email signature on iPhone. In this guide, you need to check out the steps mentioned below. Find logo or image that you will like to include in email signature. It could be on website or in photos app. Press and hold to bring up the menu and select copy. When you go back at home screen, find the settings and then click on it. In settings, scroll down until users see mail and click on it. In mail settings, you need to scroll down to the bottom and find out signature.