RATP Dev, a subsidiary of the RATP group, is rolling out holographic stop buttons on the bus network it operates on behalf of Île-de-France Mobilités and the Saint-Quentin-en-Yvelines conurbation community. The “HoloStop” system is based on the know-how of MZ Technologie, a French company. It will be tested on 5 buses starting from 07 December.