A portable electronic device is disclosed comprising: data processing means; data repository containing data representative of a digital map; and display means. The device further comprises means for, in relation to data representative of a plurality locations relevant to the digital map, providing, on a representation of the digital map displayed on the display, for each of the locations, one of a plurality of different graphical user interface (GUI) elements characterized by different prominence levels to indicate the locations, wherein the prominence level of the GUI element used for each location is dependent on the level of detail at which the digital map is displayed and a deemed relevance of that location to a user query.