In a new episode of the BBC's Panorama, Edward Snowden describes the secret mobile phone malware developed by GCHQ and the NSA, which has the power to listen in through your phone's mic and follow you around, even when your phone is switched off.
The cyberweapons are possible because of flaws in phones' operating systems and apps, and when GCHQ and the NSA discover these flaws, they weaponize them, rather than helping the manufacturers patch them. This leaves all smartphone users vulnerable to the kinds of attacks that Snowden discloses, whether they are launched by "friendly" spy agencies or spies from other countries, or criminals, or voyeurs, or nihilistic hackers who just want to screw things up for random people.
GCHQ named its weapons after Smurfs:
"Dreamy Smurf is the power management tool which means turning your phone on and off with you knowing," he said.
"Nosey Smurf is the 'hot mic' tool. For example if it's in your pocket, [GCHQ] can turn the microphone on and listen to everything that's going on around you - even if your phone is switched off because they've got the other tools for turning it on.
"Tracker Smurf is a geo-location tool which allows [GCHQ] to follow you with a greater precision than you would get from the typical triangulation of cellphone towers."
Mr Snowden also referred to a tool known as Paronoid Smurf.
"It's a self-protection tool that's used to armour [GCHQ's] manipulation of your phone. For example, if you wanted to take the phone in to get it serviced because you saw something strange going on or you suspected something was wrong, it makes it much more difficult for any technician to realise that anything's gone amiss."
Edward Snowden interview: 'Smartphones can be taken over'