New answers tagged free-sources
Depending on your level of accuracy I would suggest the following: Low level Accuracy Use QGIS for Android (free and has a gps toolbar) along with your tablet or handheld native gps High Level Accuracy Use QGIS for Android along with your vendor gps
What about this from the DIVA-GIS website and their spatial data are free. DIVA GIS
I found the site below (credit to Robin Wilson @robintw) to be very interesting. There is a description of all datasets listed and it is organized by themes. www.freegisdata.rtwilson.com Furthermore, it has been updated several times and it is as complete as I can tell.
http://www.openstreetmap.org/ has free data from the whole world. It takes some time to know how to get what you want. Geofabrik offers free downloads of regional extracts.
http://www.naturalearthdata.com/ has boundaries and stuff but it is all on a pretty low resolution. http://www.weogeo.com/ has several free datasets including openstreet map, as well some for pay.
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