The FTC has issued warning letters to mobile app developers who have installed software that can monitor a device’s microphone to listen for audio signals that are embedded in television advertisements (Silverpush). The letters were sent to 12 developers whose apps are available for download in the Google Play store and appear to include the Silverpush software.

The Silverpush code allows for the monitoring of consumers' TV habits through unique audio beacons emitted by TV, which cannot be heard by the consumer, as long as the mobile phone is in the same surrounding. The letters note that the software would be capable of producing a specified log of the television content viewed while a user’s mobile device was turned on for the purpose of targeted advertising and analytics.

The warning letters point out that the apps in question ask users for permission to use the device’s microphone, notwithstanding that the apps do not have a requirement for that functionality. However, they do not inform consumers that the app could monitor television viewing usage, even if the app is not in use. The letters also warn the app developers that if their statements or user interface state or imply that the applications in question are not collecting and transmitting television viewing habits data, when in fact they do so, this could constitute a violation of Section 5 of the Federal Trade Commission Act.

It should be noted that applicable relevant guidance was published by the FTC back in 2013 and included best practices for privacy disclosures in mobile apps.