In one aspect, information of multiple anchor points is received and stored. The information of each anchor point includes Global Positioning System (GPS) data of a particular location and radio frequency (RF) data that was obtained at a device at the particular location. A geo coordinate is determined for an indoor location based on the RF data obtained at the indoor location and the information of the anchor points. Various embodiments pertain to software, systems, devices and methods relating to anchor points and/or the obtaining of a geo coordinate for a location.