The cell phone jamming device was originally developed for law enforcement and the military to disrupt criminal and terrorist communications. The Bombs that blow up commuter trains in Spain in March 2004, as well as bombs exploding in Bali in October 2002 and Jakarta in August 2003 all rely on mobile phones to trigger explosives. According to reports, a cell phone jammer prevented assassination attempt on Pakistani President Pervez Musharraf in December 2003.

When President Bush visited London in November 2004, it was reported that British police usd jammers to protect the President's convoy through London.

In the case of hostage taking, the police can control where and when the captor can call. Police can block telephone calls during a drug attack so that suspects can not communicate.

And later cell phone blocker was spread for religious places such as temples, churches. You may find out that your cell phones have no signals in some cinemas,church,court or meeting room where a jamming device may be used.Thus, when a person forgets to turn off their mobile phone and does not have any ringing of the mobile phone, the mobile cellular telephone interfering device works well and the conference can continue quietly.Cell phone blockers can be also used in areas where radio transmission is hazardous (areas with potentially explosive gases), such as chemical storage facilities or grain elevators.

Besides,the company uses spy camera jammers to stop corporate espionage by blocking voice and photo transmissions from cameras and phones.

But it can also be used illegally and inappropriately At the more suspicious end of the spectrum of legitimacy, there are rumors that hotel chain-mounted jammers prevent guests' handsets from using and force them to use indoor phones at high rates.