When you first access MobileMyth you will be prompted to enter your backend and mythweb information. MythWeb url is there to provide access to incomplete parts of MobileMyth.
The first time you open the site on each device you own the Frontend settings page will appear. This after specific to each device.
(Right now only the tablet UI is working) Now hit home and start using MobileMyth.
Some times you will have to restart your webserver after updating the backend settings.