If you use an iPhone or iPad to email important clients, friends, and relatives, then you probably want to try to minimize as much unnecessary typing as possible.
Signatures are great for when you need to include your work address and phone number, an inspirational quote, or any other information you think necessary for your recipients to know. Signatures can make short work of adding routine and repetitive information to the end of your messages. And just like any mail client, you can easily create, edit, and assign signatures to your Apple Mail accounts on your iOS device.