The NSO Group builds tools that let people hack into the most popular smartphones and record calls and gather other data. The NSO Group builds tools that let people hack into the most popular smartphones and record calls and gather other data. While its tools are used by governments to help track down and stop terrorists, the company has been under fire for providing tech to governments that were then used to target 174 activists, journalists, lawyers, and others in abusive ways, including staff at Amnesty International.