Finding the nearest exit in Montreal's many metro stations sounds easy, and it is for certain stations like Lionel-Groulx. Others, like the subterranean labyrinths of Berri UQAM or Jean-Talon, are not so easy to navigate.
I've personally missed the 80 more than a few times because I didn't get out of Place des Arts in time.
Enter Sorties De Métro Montréal (SDMM) a smartphone app all about getting you out of the metro through the closest or most convenient exit.
The app is pretty simple and straightforward. Choose a line, a direction, then a destination, and SDMM will tell you which car to get into on the metro and which exit to leave from based on where you need to go.
Bus times aren't included in the app, but one very cool feature (aside from the ideal-exit) is a complete map of the underground city. The map outlines Montreal's underground and allows you to easily navigate the maze-like paths, telling you which paths lead where and through which stations. An invaluable asset when you're in a rush or want to stay indoors.
For more info, SURF the official website.