Custom Maps lets you track your GPS position on paper maps

Custom Maps is one of those original ideas you never thought you'd need until it was presented to you. Basically, it's an app that lets you turn any map (or an image of one) which happens to line up with region available in Google Maps into a GPS map. What the map? Okay, say you have a photo of a paper map or brochure, like these you'd find at the entrances of parks and zoos. It can even be a screenshot of a .PDF map you have laying around. What you have to do after is line up at least two, or more points that match the map image with Google Maps. If the spell works as advertised, Custom Maps will display your GPS location on the map image. Technology is amazing, isn't it?

One of the best things about Custom Maps is that it stores all your map images offline. This means the app will be able to track your position even if there's no data connection available, relying solely on GPS signal. See, apps like Google Maps need a data connection so that map data can be refreshed and updated in real time. Since you already have the complete map pictured, Custom Maps has you covered. Literally.

Additionally, Custom Maps can display the distance between your current location and a point on the map. And since the maps are stored in plain, everyday image formats, you can open your favorite image editing app and draw markings over them. X marks the spot, indeed. User maps can be shared over e-mail or hosted online and accessible via QR codes.

To top it all off, Custom Maps supports displaying of placemarks on the map. Placemarks come from Google Earth and are going to be useful to whoever is still using the program (NASA workers, maybe).

As Custom Maps is an open-source project, it probably has many a ways to go. If you feel like you have something to contribute, visit its page and grease your elbows for coding.