If you want to link your OBDeleven account to Facebook or Apple ID, you can do this in the Profile section of your mobile app.
Linking account on iOS
Open "Profile" from the menu.
Here, tap "Link" in the Account linking section.
Choose the account you want to link and proceed with the next steps to finish the setup.
Note: Account linking via Twitter isn't possible anymore.
Linking account on Android
Open "Profile" from the menu.
Here, tap the pen icon as shown below:
Choose "Link to other account" and click "OK."
Click on the account you want to link. Note: It's no longer possible to link your OBDeleven account with Twitter.