You could use one the community apps to monitor quite a few devices. I use supertiles and it allows for 8 devices per tile(possibly 16 if it fits). And then there's Tile Master as well. I don't use tile master but I believe it has more features than supertiles. This is one of several I use for lights and things but you can customize it however you like and I know quite a few people use them for contact sensors. The icons I found online somewhere.
