I decided to buy the 72h Brussels Card (museums + transport) through this app as we had to spend exactly 3 days in Brussels. We had made a calculation of the attractions we wanted to see + transport and in fact it was much more convenient to do the map. I highly recommend doing it 1) in 3 days you can really visit many museums 2) because the vehicles work perfectly and doing the day is not convenient, we have practically always used them knowing that we have included them !! The only flaw is that you have to go to the information center in Grand Place and show your voucher, from there they will print QR codes to be used in each museum indicated. As for transport: you must always go to the info center in Grand Place, they will print a 6-digit code to be entered in the red "GO TICKET" machines that you find at each bus / tram stop or in the metro, they will print the transport pass, passing it on the first vehicle will be activated!