1. A method comprising: receiving, by a mobile device, measurements of one or more environmental properties made by one or more sensors of each of one or more other mobile devices, the received measurements having been made concurrently with real-time measurements of at least one of the one or more environmental properties made by one or more sensors of the mobile device; determining, by the mobile device, that each of the one or more other mobile devices is within a locality threshold of the mobile device; determining, by the mobile device, that a difference between at least one of the real-time measurements and a metric of the received measurements corresponds to a statistical likelihood of the at least one of the real-time measurements being unreliable by analyzing the difference between the at least one of the real-time measurements and the determined metric; and based on the determined unreliability, the mobile device excluding the at least one of the real-time measurements from a location determination of the mobile device derived from the real-time measurements of the at least one of the one or more environmental properties.