Save a draft in Mail on iPhone
In the Mail app , you can save a draft to finish later, or look at existing emails while you’re writing a new one.
Save a draft for later
If you’re writing an email and want to finish it later, tap Cancel, then tap Save Draft. To get it back, touch and hold .
With OS X 10.10 or later, you can also hand off unfinished emails with your Mac. See Use Handoff with iPhone.
Look at another email while you’re writing one
Swipe down on the title bar of an email you’re writing.
When you’re ready to return to your email, tap its title at the bottom of the screen.
If you have more than one email waiting to be finished, tap the bottom of the screen to see them all.