An indicia-reading module suitable for integration within a host mobile computing device that has an integrated flexible circuit is disclosed. The indicia-reading module includes a plurality of subassemblies, each supported and electrically connected by a discrete, rigid, multilayer printed-circuit-board (PCB). A unitary flexible circuit electrically connects the subassemblies and is physically integrated between two inner layers of each subassembly's discrete, rigid, multilayer printed-circuit-board. The use of the integrated flexible circuit aids in reducing module size, signal loss, and interference with the host mobile computing device.