A mobile device is configured to wirelessly authenticate with a reader device. The mobile device may receive an acoustic signal from a user, and a command may be determined based on the acoustic signal. The mobile device may transmit the command to the reader device if the mobile device and the reader device are authenticated. The reader device may receive the command, and may analyze the command to determine an action to be performed. The reader device may then perform the action if the mobile device is authorized to request the command to be performed.