Hi @Cyberpunk_Is_Bae, thanks for the appreciation 
We’re glad you are enjoying Duo Mobile so far. Cool username, too.
it prompts me for a backup password, is there a way I can use that to log in online and view my account?
The backup password is used to recover your third-party accounts (those such as Instagram or Facebook that use TOTPs for authentication) to the Duo Mobile app when you get a new phone or change devices.
The Duo Mobile app is tied to your device’s unique hardware security module (HSM), so it is necessary to back up and restore your accounts in Duo Mobile using Duo Restore and Duo Restore for Third-Party Accounts in order to retain them across devices.
When you enable Duo Restore for Third-Party Accounts, you are prompted to create a 10-128 character recovery password, which you will have to provide again in order to restore the accounts later.
Some other important things to note: Deleting an account from the Duo Mobile app does NOT disable two-factor authentication (2FA) for that account, so it’s very important that you disable 2FA from within the profile settings of the account itself directly on the service provider’s side first, or else you will be locked out of your account.
Also, if so, is there a way to use a Yubikey or other similar token to secure my Duo account itself?
As a third-party account user, you don’t have a “Duo account” because you are not using a username and password to access a Duo-protected application, nor are you accessing Duo’s administrator interface via the Duo Admin Panel. You can learn more about the differences between what we call “third-party accounts” and “Duo-protected applications” here: https://help.duo.com/s/article/2242.
Creating a Duo administrator account will not provide you with an “overview” of your third-party accounts as those are exclusively managed by you via the Duo Mobile app and the third-party app or service it is associated with.
Let me know if you have any other questions!
