Ctrl+6 works for '^'.
I also found "Menu -> Palettes"
There seems to be some other thing to, e.g
- "Edit->Preferences" doesn't exist.
- auto-completion does not exist
- suggestion bar doesn't exist
But I can live with that. Overall Mathematica seems to work fine, and I like it!
I don't know the version number of raspbian, it is the latest. Linux version 3.18.7-v7+ "cat /proc/version"