Let's cut the Ubuntu rope getting a complete different name. We are not a subdivision of Canonical!
How about Ubantu? 😉

Thinking about something with pirates because it's bad ass just like I feel when using Ubuntu Touch.
Unfortunately Black Flag is already taken.
Pirate OS is too obvious, kinda childish. Good name for a raspberri pi operated mobile.
How about Keelhaul? Or Mutiny which is also a geeky reference to the TV Show "Halt and Catch Fire"? Think that was also considered for Yunit afaik.
Peg Leg MOS (MOS == mobile operating system), three "words" with 3 letters - sounds catchy.