A journaling subsystem on a mobile device stores event data related to applications or other subsystems running on the mobile device. The event data can be stored and indexed in a journal database so that a timeline of past events can be reconstructed in response to search queries. In some implementations, a timeline can be reconstructed with markers on a map display based on search results. When the user interacts with a marker on the map display, the event data collected by the mobile device is made available to the user.