PrivateGSM does not protect from mobile spywares, however outbound calls with PrivateGSM may not be tapped by spywares due to a feature of smartphone operative systems.
Simplifying, only one application at a time may access the mobile microphone: if PrivateGSM is set on “secure call” mode, the spyware may not tap the coded call.
If, on the other hand, the spyware is already tapping a mobile phone, on which PrivateGSM is then installed, it will not be possible to execute coded calls as this application may not access the microphone used by the spyware.