Tandem Access intends to offer the visually impaired an instrument relying on the latest technological advances that makes underground travelling in Bucharest much safer. The app works like a guiding system that makes use of a network of iBeacons installed in the stations. Once the user gets close to the station, the app needs to be open and it will announce major locations inside the station (ticket control, stairs, major intersections, platform, etc.). Taking into consideration the direction from which the user is coming, the app will list the options available to the user for reaching a specific train platform or exiting the station in a specific location. The user should remember that, in order for the app to give correct directions, it needs to be opened early and kept open throughout the journey, as it relies on the communication with at least 2 beacons to calculate the direction in which the passenger moves.