I don't think one is much harder than the other (since solver algorithms already are a solved problem), the hardware seems more impressive to me than whether you put software on it that tracks and reverses movement or has a solver algorithm in it.

From the video it looks like a solver algorithm by the way, and not going for least amount of movements either, it seems to move much more during the solve than the movements the person did. To save battery they should go for optimal amount of moves!