In one embodiment, in response to a user application request to determine a location of a user-device having a Wi-Fi radio, the Wi-Fi radio is triggered to transmit a request to Wi-Fi access points within range. Messages are received from the Wi-Fi access points, each message identifying the Wi-Fi access point sending the message. Signal strength of the messages received from the Wi-Fi access points is calculated. A reference database of stored locations for Wi-Fi access points in a target area is accessed to obtain the stored locations for the identified Wi-Fi access points. Based on the number of the identified Wi-Fi access points identified via received messages, a corresponding location-determination algorithm is chosen from a plurality of location-determination algorithms. The location of the user-device is determined using the stored locations for the identified Wi-Fi access points, the signal strengths of the received messages and the chosen location-determination algorithm.