Techniques describe opportunistically capturing and tagging images with wireless information by a mobile device. The tagged image may be transmitted to a remote server, such as a crowdsourcing server, where the location at which the image was captured may be determined using visual features from the image. An association between the location and the wireless measurements may be used in building/maintaining a heatmap. In one embodiment, techniques are described for setting camera parameters for opportunistically capturing images and may include receiving at least one signal associated with at least one signal emitting device, determining information associated with the at least one signal emitting device using the at least one signal, setting at least one camera parameter for a camera coupled to the mobile device based on the information associated with the at least one signal emitting device, and capturing one or more images using the at least one camera parameter.