As far as I can tell, this is basically an ion thruster, though I've never heard ion thrusters called Hall-effect thrusters before, so this may be a somewhat atypical sort of them. It ionizes gas to propel itself. The EM drive was basically a microwave in a sealed container that was hoped/theorized to create thrust through an unspecified/unknown mechanism, with no reaction mass coming out the back of the craft.
The Hall-effect thruster is a specific type of ion thruster. By far I am not an expect, but the Hall-effect is has something specifically to due with the movement of electrons creating a current in the thruster, which I believe causes the ionization. Others ionize the propellant by bombarding it with electrons to create the ionization.
And as another commenter pointed out, this is not the first ion thruster on a cubesat.
Compare https://en.wikipedia.org/wiki/Hall-effect_thruster to https://en.wikipedia.org/wiki/EmDrive