1. A method of estimating a likelihood of a Wi-Fi enabled device being located within an estimated geographical area, the method comprising: identifying at least one Wi-Fi access point in range of the Wi-Fi enabled device based on signals received by the Wi-Fi enabled device transmitted by the at least one Wi-Fi access point; consulting a reference database to determine for the at least one Wi-Fi access point from which signals were received a last-known position of the at least one Wi-Fi access point and time information associated with said last-known position for describing a most recent time when the at least one Wi-Fi access point was observed to be at the last-known position; estimating a geographical area in which the Wi-Fi enabled device may be located; and estimating the likelihood of the Wi-Fi enabled device being located within the estimated geographical area based on a probability that the at least one Wi-Fi access point has relocated, the probability that the at least one Wi-Fi access point has relocated based on at least one of: the most recent time when the at least one Wi-Fi access point was observed to be at the last-known position as indicated by the associated time information, or a number of the one or more Wi-Fi access points from which signals were received by the Wi-Fi enabled device, wherein the likelihood of the Wi-Fi enabled device being located within the estimated geographical area quantifies a probability that the estimate of the geographical area is correct.