Snowden has referred people to the CIA standards for secure telephones: Baseband limited to data only, VPN&#x27;ed into VoIP server to make&#x2F;receive phone calls. I believe he was still using Android to do this.<p>Any smart person would get a cheap chinese knock-off phone based on a MediaTek MT6592 with a bunch of RAM, install vanilla linux on it, and run YateClient or Plasma Mobile. Combined with VPN, data-only, and VoIP, this would be an enormous pain for anyone to be able to properly track.