The American Civil Liberties Union of New Jersey has released an Android app designed to be used by people who want to secretly record police activity without running the risk that the mobile device will be seized.

Called Police Tape, the free app allows the user to record video and audio discreetly. For one thing, the app disappears from a phone's screen when the recording begins. For another, it can send a copy of the recording to the ACLU-New Jersey for backup storage and analysis of potential civil liberties violations. 

It is similar to the Stop and Frisk Watch app for Android released last month by the New York Civil Liberties Union, which stops filming when the device is shaken and alerts people when other app users in the area are recording police activity. Both apps also provide legal information about citizens' rights when dealing with police.