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I was wondering if there are shapefiles for postcode regions in India.
I did find some shapefiles that give the outline of the administrative units in the country but not with postcodes. Right now I am using Google Map API that highlights the region under pin-code.
It looks like the information is not present in public domain. It looks like either you can crowdsource the information or buy it from a thirdparty called MapMyIndia.
I found a blog by Anand.S where he wrote about his crowdsourcing idea. Other than this I couldn't really find anything interesting: mapping-pin-codes