A traditional clicker can be used for changin between slides in regular presentation mode. But not in Mentimote.
This feature should be added so that the presenter at e.g. conference lectures can have a screen towards himself with Mentimote (which shows next/previous slides, incoming comments etc. and allows for extra controls) on which he can shift between slides without having to press a keyboard key and without having to use a smartphone as a remote control (both of which are unprofessional methods in a stage setting of on-location presentation).