A mobile device for detecting an electrical signal generated by an ingestible event marker is disclosed. The mobile device includes a detection subsystem to receive an electrical signal generated by an ingestible event marker from a detection arrangement. A processing subsystem is coupled to the detection subsystem to decode the electrical signal. A radio subsystem is configured to transmit the decoded electrical signal to a wireless node. A system includes the mobile device and the detection arrangement. A method includes receiving the electrical signal generated by the ingestible event marker at the mobile device, decoding the electrical signal to extract information associated with the ingestible event marker, and transmitting the information to a wireless node.