A method of monitoring swimming activity includes: determining at least one of an actual relationship of a mobile device to water or an expected relationship of the mobile device to water; determining ranges to satellites, based on signals received by a satellite positioning system (SPS) receiver of the mobile device, in response to the signals being received by the SPS receiver when the at least one of the actual relationship of the mobile device to water or the expected relationship of the mobile device to water is a desired relationship of the mobile device to water; and determining a location of the mobile device based on the ranges to the satellites.