This article presents an Android application for safety driving based on OsmAnd, an open source platform offering offline maps and navigation. Our application extends OsmAnd to achieved smart navigation features by creating a network of vehicles. These features allow informing regular vehicles about incoming emergency vehicles, which include ambulances, police cars and fire brigades. The goal is to alert the driver in a timely manner so that he can take navigation decisions based on the information received. For proper operation, the application relies on message dissemination in the scope of a vehicular ad-hoc network, a goal that is achieved with the support of our proposed GRCBox hardware. By running on top of GRCBox, our application is provided with V2V communication abilities despite running on off-the-shelf Android terminals. Based on performance results obtained in restrictive urban canyon scenarios, we find that the application is able to reach, in the worst case, vehicles located near the intersection from streets located up to 80 meters away from the sender. By setting the message sending rate to 10 Hz, we find that the inter-packet arrival time is between 100 ms to 900 ms, meaning that notifications will reach other vehicles in less than 1 second.