One morning within the drab walls of a Texas prison, the warden is sifting through his mail. He finds a letter addressed to him from an inmate’s mother. When he rips it open, the message inside is momma complaining about the poor reception on her son’s cellphone.

For the warden, this is more alarming than amusing. Inmates’ growing accessibility to cell phones has become a serious problem for prisons. Authorities say that inmates are using the phones to buy drugs, intimidate witnesses, plot escapes, or oversee organized crime. But with a budding market of small-scale cell phones that are designed to avoid detection by body scanners, phones have never been easier to smuggle into prison intra-anally.

Among the most popular prisoner cells is the world’s smallest mobile phone, the Zanco Fly. The Fly has a screen size of 0.66 inches and is about the same size as a pocket lighter. But if you're really wondering what edge the Zanco Fly has over the latest touchscreen smartphones, try shoving an iPhone 7 up your ass.

The Fly’s marketing seems to indicate that the cell phone was devised for butt-smuggling. For instance, Zanco claims that the Fly is 100 percent plastic, a perfect feature for beating simple metal detectors. Newer versions also boast a built-in voice changer and often come with a "beat the BOSS" tagline, claiming that the cell is undetectable by body orifice scanners.

Amazon customer reviews for assorted tiny phones range from the subtle to the straightforward. One reviewer reports that the cell is "very small and easy/painless to hide." Other users, however, are far more blunt. In a five star review voted "helpful" by 60 people, the reviewer comments, "No anal problems!!! Didn't hurt my bum at all, thanks guys. :)"

Some prisoners use their cell phones for purely innocent purposes — like when two inmates at a prison in Birmingham were given an extra nine months each for using their smuggled cell to shoot a rap video from inside their cell. But it would be naive to assume that these phones are never used for illicit purposes.

For this reason, nearly all prisons and jails have policies forbidding inmates to have cells phones. Several states have even made it a crime, and are looking to raise that crime to a felony level.

Whether they’re looking up the home address of their least favorite guard, organizing a riot, or even buying jewelry with stolen credit card numbers, prisoners with bandwidth pose a host of challenges.

''If these guys were just calling their girlfriends, it wouldn't be such a problem, an anonymous senior law enforcement official told the New York Times. “But we are concerned about cell phones being used for drug deals and arranging crimes.”

What’s more, wired inmates diminish the entire concept of incarceration. Instead of being punished and isolated, a prisoner with a cell phone can organize murders, threaten witnesses, plot crimes, and browse the web to determine which escort to order up for the next conjugal visit.

But perhaps we can relate with the inmates’ emotional segregation. If someone told you that you couldn't speak with your loved ones whenever you wanted, wouldn’t you shove a phone up your butthole, too? Considering the sheer panic most of us experience when our battery drops below 20 percent, you’d probably be eyeing a bottle of lube if you were facing a single day without your cell.

So it seems cell phone butt smuggling is a natural reaction for these disconnected convicts. You’d have to be a huge asshole not to empathize.