When you first logon to iMIMS it requires the Internet to validate your credentials.
To achieve that iMIMS must be allowed to use the Internet: Please follow these steps: Settings, Mobile, scroll down to the “Use Mobile Data For” section and turn it on for iMIMS.
You must also be connected to the internet.
After that when you open the iMIMS app it will logon automatically – even though the login page is displayed it will logon automatically. It will even logon automatically in flight mode.