You can minimize email drafts and save them for later.
If you're typing an email, simply tap the area where the subject line is and drag it down to the bottom of your screen. Now your email is minimized at the bottom of your inbox, and you can tap it again at any time to access it. This makes it easy to switch back and forth between your inbox and the message you're working on.
Use gesture shortcuts, such as swiping to the right on any email to mark it as read.
There are a few handy gesture shortcuts in your iPhone's Mail app that make it easier to clean up your inbox. You can automatically mark a message as read without having to open it by swiping to the right on any email. You'll see the blue box that says "Mark as Read," as shown in the picture to the right.
If you swipe to the left on any email, you'll get another menu of choices.
If you don't want to mark an email as read but still want to move it, try swiping to the left on any email. This will bring up a few choices, such as flagging an email or archiving it.