@linuxlion Ubuntu Touch is a read only file system to stop clowns like me breaking it by doing something stupid. You have no idea how 'inventive' I can be.
If you are more experienced you can make the system read/write either from the command line or you can use the UT Tweak Tool from the Openstore to do it. Just be careful what you do.
I believe that apt Is not supported/recomended.