1. A method, comprising: determining, by at least one computing device, a first location based on a history of locations visited by a mobile device; after determining the first location, determining a location of the mobile device; calculating, by the at least one computing device, a risk score depending upon a distance between the location of the mobile device and the determined first location; either approving or rejecting a financial transaction requested by the mobile device based on the risk score, such that if the risk score indicates a greater distance, the financial transaction is approved, and if the risk score indicates a smaller distance, the financial transaction is rejected; and sending first data to the mobile device indicating whether the financial transaction is approved or rejected.