Microsoft today announced that they are updating OneDrive on iOS to support password managers. You can now sign into the OneDrive app on iOS automatically if you are using LastPass or 1Password.
Here is how it works,
1. Launch OneDrive and sign in
2. Tap the icon in the upper right corner
3. Select your password manager (or enable them if you have not)
4. Log into the password manager (I have Touch ID set up for mine)
5. Boom! That’s it.
This feature is based on the new iOS 8 feature where applications can to talk to other applications via extensions.
Source: OneDrive blog