According to Kim, authorities monitor all text messages — along with location data — in real-time, while voice calls are recorded, transcribed, and stored for three years. One former North Korean security agent told him officials refer to cell phones as "cowbells" and refuse to carry them. "All the defectors I interviewed agreed users would never say anything politically inappropriate via cell phone, believing every call is monitored," Kim said.
North Korean cell phones, of course, don't offer Internet access. And the basic 200-minute, 20-text plan that comes with a phone is so expensive to "top off" that some people buy a second phone under a fake name just for the extra minutes (Only the wealthy can afford a phone to begin with. Mobile devices can cost hundreds of times the average citizen's monthly salary.)
Most people, however, own cell phones as a status symbol and use camera, video, and game functions more than actual calls. "An increasing number of cell-phone users in North Korea use their cell phone not as a communications device, but as a personalized entertainment system," said the U.S.-Korea Institute's Alexandre Mansourov.
If outside content — such as a South Korean soap opera — is found on a device, "an officer can confiscate a phone on the spot at his discretion and users can be sent to labor concentration centers," Kim said. And as citizens have learned about data transfer, the government has issued new models with fewer functions and forced citizens to return their phones so they can disable features like Bluetooth.
Meanwhile, the government has found a convenient tool to spread its message. Cell phones offer access to the state newspaper (whether that's via an application or MMS messages is in dispute). The ruling party also sends near-daily group texts updating users on Kim Jong Un's doings.
Though Koryolink covers a small fraction of the country's land mass, it reaches 94 percent of its people. Expanding service to North Korea's rural, less-populated areas would likely do little, according to a Korea Economic Institute report earlier this year. "In these remote areas where electricity is stored in car batteries and used to heat water, keeping cell phones charged is not a priority," wrote Scott Thomas Bruce, an associate at the East-West Center.
While cell-phone use is tightly controlled and monitored, Internet access is far worse. Only the privileged can use Kwangmyong, a state-run intranet that offers only approved media and closely watched chat and discussion boards. As for the actual Internet, as few as a dozen "super-elite" North Korean families can access it within the country, according to Bruce's report.
Some university students and state officials whose job it is to collect information on the country's enemies are also granted Internet access, again very limited and closely monitored.