Whisper Systems, a California company that specializes in data encryption, mostly caters to businesspeople with trade secrets. But when the Arab democracy movement ignited this year, the company handed out its security software to Egyptian protesters free of charge.

The company’s Android mobile phone applications RedPhone and TextSecure encode calls and text messages, protecting them from hackers, competitors – or in this case government surveillance.

Whisper donated this software for a simple reason: Founders Moxie Marlinspike (his official alias) and Stuart Anderson say they’re committed to creating a world where people can discuss politics without fear of government reprisals.

Just as new technology makes communicating around the world easier than ever, phones, e-mail, and websites make snooping a breeze as well. This year, Beijing began using cellphone GPS systems to track and suppress political demonstrations. A March raid on Egypt’s state security headquarters revealed that former President Hosni Mubarak’s regime closely monitored the e-mail accounts and text messages of known political activists.

Such events underscore the privacy threats posed by digital communication, says Mr. Marlinspike, a programmer who publicly demonstrates such vulnerabilities at computer-security events such as the annual Black Hat Conference.

“People think about the Internet as having this democratizing and horizontalizing effect,” he says, “but the infrastructure itself is not horizontal or decentralized.” Companies own the wires and servers that make up the Internet. “It is highly controlled by a small group of people.”

Troubled by the possibility that technology will empower Big Brother, Marlinspike and Mr. Anderson view encryption technology as a way to push back against government spying.

That’s why, when the Egyptian uprising broke out in January, Whisper changed its encryption scheme to work in the Middle East. For two weeks, the pair worked 10- to 12-hour days to ensure that their programs would be accessible to Egyptian activists during the government crackdown.

Eager to assist democracy movements throughout the world, Whisper Systems wants to expand its humanitarian operations beyond Egypt and to provide its software to activists in nations like Belarus, where opposition movements have been forced underground.

Most cellphones lack strong encryption, so dissidents take severe risks when they use them to communicate, especially in countries where antigovernment speech is criminalized, says Katrin Verclas, co-founder of MobileActive, a global network that uses cellphones for social change.

Cellphone technology easily hacked

Hackers have found many ways to break into the Global System for Mobile Communications (GSM), the network technology used by most of the world’s cellphones, including those on AT&T and T-Mobile. Last year, coders released software capable of cracking the encryption algorithm used by many GSM phones, and in December a group of researchers in Berlin publicly demonstrated ways to eavesdrop on GSM calls with relatively inexpensive and unsophisticated equipment.

While companies and academics work to plug these holes, Ms. Verclas says Whisper System’s programs are particularly valuable since they provide high-quality encryption.

However, most encryption programs are so complex and obscure that many people don’t bother using them. RedPhone and TextSecure are more intuitive than their predecessors, Verclas says, and thus more likely to be used.

According to computing researcher Christopher Soghoian, the increased accessibility of Whisper Systems’ software is critical for mass movements.

“Other encryption technology is not simple enough for my grandma to use, and that’s a problem,” says Mr. Soghoian, a graduate fellow at Indiana University’s Center for Applied Cybersecurity Research. “Everyone is susceptible to the weakest link in the chain, and in this case, the weakest link is the person that isn’t using the technology.”

In Soghoian’s view, programs such as RedPhone and TextSecure are long overdue. “There are human rights activists for whom arrest is a routine part of their existence, and they are in desperate need of these technologies,” he says.

Armenian opposition leader and former ambassador to the United States Alexander Arzoumanian is one such activist. He says many like him would use Whisper Systems’ software if they were convinced that it worked. Mr. Arzoumanian’s yearlong imprisonment, based on wiretapped phone calls, has convinced him that encryption software could be invaluable for dissidents in countries like his.

Arzoumanian describes Armenia as a place where spying is so pervasive that there is little, if any, distinction between public and private life. He says he is so accustomed to being monitored that he was not surprised when government officials released transcripts of his telephone conversations to the press, and his private communications were published.

Protection from spies, in the form of encryption, would be a welcome change in Armenia, Arzoumanian says.

“If people know they are under surveillance 24 hours a day, they are afraid to speak out,” he says. “They hate the idea that someone is listening to them. It would be good to have places where people feel free to talk.”

Could encryption hinder activists?

Not everyone is enthusiastic about activists’ use of encryption software, including Gene Sharp, a Harvard University researcher who is widely considered to be the foremost expert on nonviolent revolutions.

Mr. Sharp’s seminal work, “The Politics of Nonviolent Action,” has been used as a guidebook in many successful people-powered movements, including the Eastern European overthrow of communism and – more recently – the Egyptian protests that toppled Mr. Mubarak.

Sharp believes that encryption might hinder activists more than help them. “Anonymous speech assumes fear and encourages fear, and fear is fatal for a strong movement of nonviolent struggle,” he says.

Because secrecy also limits the number of people who have access to knowledge, Sharp says it is an impractical tool for mass movements. He argues that the protests in Cairo earlier this year would not have attracted as many people or have been as effective as they were had they been organized secretly.

According to Sharp, public and courageous protests like those in Egypt are the best way to destroy a repressive regime that relies upon fear for power. “There are situations where protesters have … good reason to be afraid,” he says, “But if you are trying to do more than save an individual, if you want to free an oppressed people, then you must be open.”