Systems, methods, devices, server computers, storage media, and instructions for prioritized device action triggered by device scan data are described. In one embodiment, a mobile device performs a method that involves executing a messaging application with an image capture interface and a scanning input. An associated scanning mode comprises capture of scan data from a plurality of input/output modules of the first client device, analyzes the scan data to identify one or more scan data patterns by matching at least a portion of the scan data against a set of data patterns, and selects a priority system action based on the results of the matching of the portion of the scan data against the set of data patterns. In some embodiments, the priority system action is selected based on a priority ranking for identified scan data types.