The 35-year-old also spoke of the NSO Group, the Israel-based company known for its Pegasus spyware.
The software has been pinpointed by independent experts as likely being used in a number of countries with poor human rights records.
“The idea is that companies like this increasingly are popping up all around the world,” Snowden said.
In one case, international experts investigating the disappearance of 43 students in Mexico in 2014 were targeted with the spyware after it had been sold to the government, the experts said.
NSO Group says its product is intended to be used only for investigating and preventing crime and terrorism.
It says it investigates allegations of improper use.
Snowden, a former contractor with the US National Security Agency, leaked thousands of classified documents to the press in 2013 which revealed the vast scope of surveillance of private data put in place after the 9/11 attacks.