On your device, tap Settings > Mail, Contacts, Calendars > Add Account > Microsoft Exchange. In the E-Mail and Username boxes, ...

Microsoft Online Services

On your device, tap Settings > Mail, Contacts, Calendars > Add Account > Microsoft Exchange.
In the E-Mail and Username boxes, enter your e-mail address. Your e-mail address and your username are the same.
In Password, enter your password, and then tap Next.
In the Server box, enter Exchange ActiveSync server name, and then tap Next.
Tap Save.
If you're prompted to create a passcode, tap Continue and enter a numeric passcode. If you don't set up a passcode, you can't get your
e-mail on your device. You can set up a passcode later using Settings > General > Passcode Lock.
Tap Close.

Learn more

Lync
Send instant messages and make calls.

Go to the App Store, and search for Microsoft Lync 2010 for iPhone.
Tap the Free button, then tap Install and enter your App Store Apple ID and password.

When the app is installed, it appears on your home screen.

Start the Lync 2010 app, and on the sign-in screen, enter your Office 365 user ID and password, and then tap Sign In.

Access your documents and sites

On your phone, open your browser.
Type your site address into the web browser address bar.
Tip Your team site address using the default Office 365 domain looks like

http://[YourDomain].sharepoint.com

Your team site address using your own custom domain looks like

http://[YourDomain].com
On the Office 365 sign-in page, sign in with your Office 365 user ID and password.
Tip To make it easier to return to your site next time, add the site to your web browser favorites.
Learn more

On the Subscriptions page, find {DB_MT_OFFER_NAME}, and then click More to confirm that your subscription ID is {DEL_SUBSCRIPTION_NUMBER}. ... On the Subscriptions page, find {DB_MT_OFFER_NAME}, and then click More to confirm that your subscription ID is {DEL_SUBSCRIPTION_NUMBER}. ... On the Subscriptions page, find {DB_MT_OFFER_NAME}, and then click More to confirm that your subscription ID is {DEL_SUBSCRIPTION_NUMBER}. ... On your device, tap Settings > Mail, Contacts, Calendars > Add Account > Microsoft Exchange. In the E-Mail and Username boxes, ... On your device, tap Settings > Mail, Contacts, Calendars > Add Account > Microsoft Exchange. In the E-Mail and Username boxes, ... On your phone, in the App list, tap Settings and then tap email + accounts . Tap add an account > Outlook . In Email address ... On your phone, in the App list, tap Settings and then tap email + accounts. Tap add an account > Outlook. In Email address ... On your phone, in the App list, tap Settings and then tap email + accounts. Tap add an account > Outlook. In Email address ... On your phone, in the Applications menu, select Applications > Mail . Select Create a new mailbox to start the setup wizard. ...