Methods, computer program products, and systems are presented. The method computer program products, and systems can include, for instance: examining data of a plurality of traveling users, wherein at least some of the plurality of traveling users have associated mobile client computer devices, and determining, by machine logic, based on the examining that certain traveling users of the plurality of traveling users are traveling in a group; deciding, by machine logic, based on the determining that one or more action is to be performed, wherein the deciding is in dependence on a processing of historical data, the historical data specifying activities of the certain traveling users when the certain traveling users travel in a group; and providing one or more output for performance of the one or more action.