Set up Exchange ActiveSync on your iPhone, iPad, or iPod touch
When you add your Exchange ActiveSync account, you can sync your Mail, Contacts, Calendars, Reminders, and Notes with your iOS device.
Add your Exchange account
Tap Settings > Passwords & Accounts > Add Account > Exchange.
Enter your address
Enter your email address. You can also enter an account description.
Connect to the Exchange Server
After you enter your email address, choose Sign In.
If the below screen appears enter the following details
Domain: Leave Blank
Username: Enter your email address example firstname.lastname@example.org
Sync your content
You can sync Mail, Contacts, Calendars, Reminders, and Notes. When you're finished, tap Save.
Edit your Exchange settings
Tap Settings > Passwords & Accounts, and select your Exchange account. You can also set up automatic out-of-office replies, and change how often you want Mail to sync.