Note:
Make sure that you have downloaded and installed the seventhings App.
You can find how to do it here.
seventhings
As soon as you open the app, you will land on the welcome page where you have to enter the URL of your seventhings instance.
Once you have entered the URL, a screen will open for your login details in seventhings, i.e. your e-mail and password.
Please make sure that everything is entered correctly, as this is the most common cause of a failed login.