In order to Sign in with Twitter (or with any other social network) to Hopscotch, you will need to enable login access for those accounts. To enable login access, please follow the steps below.
First, log in with your Hopscotch account email and password at the bottom of hopscotch.social/login.
Click Manage Accounts in the top right drop-down menu of your dashboard.
On the Manage Accounts page, click on the icon located to the top-right of the account you want to enable login access for.
Click Enable Login Access on the drop-down menu that opens.
To disable login access, follow the same steps above, except click Disable Login Access in the last step.