An anonymous reader writes: The Tor Project recently announced the release of its prototype for a Tor-enabled smartphone—an Android phone beefed up with privacy and security in mind, and intended as equal parts opsec kung fu and a gauntlet to Google. The new phone, designed by Tor developer Mike Perry, is based on Copperhead OS, the hardened Android distribution profiled first by Ars earlier this year. "The prototype is meant to show a possible direction for Tor on mobile," Perry wrote in a blog post. "We are trying to demonstrate that it is possible to build a phone that respects user choice and freedom, vastly reduces vulnerability surface, and sets a direction for the ecosystem with respect to how to meet the needs of high-security users." To protect user privacy, the prototype runs OrWall, the Android firewall that routes traffic over Tor, and blocks all other traffic. Users can punch a hole through the firewall for voice traffic, for instance, to enable Signal. The prototype only works on Google Nexus and Pixel hardware, as these are the only Android device lines, Perry wrote, that "support Verified Boot with user-controlled keys." While strong Linux geekcraft is required to install and maintain the prototype, Perry stressed that the phone is also aimed at provoking discussion about what he described as "Google's increasing hostility towards Android as a fully Open Source platform." Copperhead OS was the obvious choice for the prototype's base system, Perry told Ars. "Copperhead is also the only Android ROM that supports verified boot, which prevents exploits from modifying the boot, system, recovery, and vendor device partitions," said Perry in his blog post. "Copperhead has also extended this protection by preventing system applications from being overridden by Google Play Store apps, or from writing bytecode to writable partitions (where it could be modified and infected)." He added: "This makes Copperhead an excellent choice for our base system." The prototype, nicknamed "Mission Improbable," is now ready to download and install. Perry said he uses the prototype himself for his personal communications: "E-mail, Signal, XMPP+OTR, Mumble, offline maps and directions in OSMAnd, taking pictures, and reading news and books." He suggests leaving the prototype in airplane mode and connecting to the Internet through a second, less-trusted phone, or a cheap Wi-Fi cell router.