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I'm trying to find a
.shp file that not only includes international land boundaries, but also the water boundaries, extending out to international waters. Does such a thing exist? I'm not even sure of what terms to search for.
Currently, I'm operating using a world borders map which is mostly good, but when our mobile users approach the ocean and their GPS flakes out a bit, our system can't place them within a country. I figure the best way to fix this is to used a dataset that will always place the national border well away from dry land (and cell towers for their phone).
This project isn't making any money, so I'm hoping for free :-)