The FBI had a problem. For years, serious organized criminals have been using encrypted phone companies such as Phantom Secure, Sky, and Ciphr to talk to their associates. These phones, which sometimes strip out GPS functionality and offer remote wipe features in case the devices are seized, helped criminals do business, but aren't perfect.
Last year, French authorities penetrated one of these services and were able to read millions of encrypted messages that led to hundreds of arrests across Europe. The FBI's plan was even more bold. Rather than penetrate an existing encrypted phone company used by criminals, it would secretly start and market its own encrypted phone firm. While criminals used the devices, the FBI would be able to read what they were saying.
The challenge was that running a fake encrypted phone company was not that different from running a real encrypted phone company.