The demo lighthouse theme works great on my mobile phone, that is I see a 'mobile' version of the site there... But on my installation, I see a pretty broken version of the way it would show on a computer. So, do I have to go somewhere to enable the mobile version/mobile detection? Tks!
What you are probably seeing is the responsive version but when you view it with the demo frame, the site shows in full view. If you'd want such, go to template settings and turn 'Responsive Layout' to Off.