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Duo - How does it work on an iPhone

Home / Help and Advice / Accounts and Security / DUO 2 Factor Authentication / Duo - How does it work on an iPhone

The Duo Mobile application makes it easy to authenticate — just tap “Approve” on the login request sent to your iPhone. You can also quickly generate login passcodes, even without an internet connection or cell service.

Find the latest version of Duo Mobile in the App Store.

Supported Platforms: The current version of Duo Mobile supports iOS 9.0 and greater. Older releases of iOS can install Duo Mobile version 3.16.7 from the App Store.

To see which version of Duo Mobile is installed on your device, go to the iOS Settings menu, then scroll down and tap Duo Mobile. The "System Info" section shows the app version.

Duo Push

Duo Push is the easiest and quickest way of authenticating. You'll get a login request sent to your phone — just press Approve to authenticate.

If you get a login request that you weren't expecting, press Deny to reject the request. You’ll be given the ability to report it as fraudulent, or you can tap It was a mistake to deny the request without reporting it.

Touch ID

Duo Mobile 3.7 and later for iOS also supports Touch ID for Duo Push-based logins as an additional layer of security to verify user identity. If you're using a Touch ID capable iOS device you'll see a Touch ID prompt each time you authenticate via Duo Mobile (if required by your administrator).

Duo Mobile TouchID Prompt

If you're not able to scan your fingerprint using the TouchID sensor you can also approve the Duo authentication request using the device's passcode (the same one you use on the iOS lock screen).

Duo Push and Notifications

You can respond to Duo Push requests from the iOS lock screen or banner notification starting with Duo Mobile version 3.8

Swipe left on the lock screen Duo Mobile notification to reveal "Manage", "View" and "Clear" actions. Tap "View" and unlock your iPhone to open up the Duo Mobile app and either "Approve" or "Deny" the request.


Swipe down on the Duo Mobile banner notification received when your screen is unlocked to approve or deny the request.

If you missed the banner notification you can still approve the Duo request. Swipe left on the missed notification in the notification tray to approve or deny the authentication request.


Apple Watch

See our Apple Watch guide.


Just tap the key button to generate a passcode. This works anywhere, even in places where you don't have an internet connection or can't get cell service.