OctoPi and OctoPrint are killa. I love it. It's especially great when you want to control multiple 3D printers from the one interface.
The only thing that I didn't like is the mobile interface - which was non-existant. That's where TouchUI for OctoPrint fits in.
It can be installed a 2 ways, one through the command-line and 2 using the plugin manager.
To install it from the OctoPrint command-line type:
~/oprint/bin/pip install "https://github.com/BillyBlaze/OctoPrint-TouchUI/archive/master.zip"
Restart the OctoPi and you're done.
From reading I only thought that the new interface should only kick in when below a certain resolution, but it has seemed to replace the interface altogether. I prefer this, but others may not.
Link: TouchUI website