International police bust: More details revealed about the app that brought down gangsters

Police have revealed more about the single app used to snag some of the international underworld's most infamous organised criminal groups and gangsters.

The Australian Federal Police has posted new videos detailing just what was on the encrypted communications devices authorities introduced onto the black market in a bid to reel in criminals.

It shows the modified devices, which look like regular cell phones, could not make telephone calls or receive text messages.

Bogus applications were also installed on it to make it appear like a cell phone.

The app used by those who had one of these devices - known as Anom - was accessed via the calculator on the device.

The devices could only be purchased on the black market and through someone who had introduced buyers to them.

AFP assistant commissioner Nigel Ryan says police were surprised how much users trusted the app and device implicitly.

"If they're talking about cocaine, they say cocaine. If they're talking about weight measurements, they talk about weight measurements.

"If they're talking about money, they're talking directly about the exact amount," he said.

"These are not coded conversations. They're black and white."

The app Anom used on a communications device that has snagged organised criminal groups around the world, including in Australia and New Zealand. Photo / Australian Federal Police

For law enforcement to get the app into the criminal circles, the app was unwittingly distributed by fugitive Australian drug trafficker Hakan Ayik, after undercover agents gave him a handset, the ABC reported.

Ayik recommended the app to criminal associates who would purchase the handset pre-loaded with Anom on the black market, the ABC reported.

'It's like Whatsapp, but it was totally compromised'

For more than 18 months, Anom's criminal users unknowingly communicated on the system operated by FBI agents.

There were 57 devices being used in New Zealand, each for criminal needs, National Organised Crime Group director detective superintendent Greg Williams said yesterday.

Tech commentator Paul Brislen says the devices are phones that run on the same network as normal mobile phones, but the only thing that can be installed on them is the app.

"It's much like Whatsapp. That means it should be very, very secure but, of course, it wasn't. It was totally compromised from the very outset."