When it comes to email on your iOS device, you have the choice to use either the native Mail app or use a third party email client like Gmail or any other. Many people prefer to use the Mail app on their iPhone, iPad and iPod touch.
But there's one nagging problem with the Mail app. When you send an an email to someone, that email address is stored on your device in the recent recipients list. Whenever you start composing an email, you could be presented with a long list of email addresses that you might never need again. So, how to remove emails from that list? Besides restoring your iOS device, here's an easy solution to do this.
Step 1: Start composing an email in the Mail app.
Step 2: In the "To" field, enter a letter or name and you will see some suggestions populate there. Scroll through that list until you find the address that you want to remove and then tap on the blue arrow next to it.
Step 3: Now you will be able to see the details of that contact. Tap on "Remove From Recents" button to remove the email permanently. This email won't be displayed any more in your recent recipients list.
Just in case if you want to add that address to your contacts, then tap on "Create New Contact" button.
If you have already added that email to your Contacts list, then this method won't work. Then you'll need to remove that entire contact.