Snowden helped design an app that turns your old phone into a surveillance device to help solve the "evil maid" problem

[Enkita]

@fuzzyfungus

The major concern here would seem to be the fact that old and/or cheap Android devices tend to… leave something to be desired… when it comes to security; and in ways that aren’t readily fixed short of a full firmware upgrade that they will never receive because their blobby BSPs have been completely abandoned and certainly never upstreamed.

I suggested using BB10 devices above, but a better answer might be to choose one of the AOSP distros and a few popular phones, then produce images which simply have many of the attack vectors omitted, including the Play Store, mail client, and a few other things I can’t immediately call to mind. I’m thinking of the hardened version of Xubuntu I designed some years ago whose job was to collect SNMP data and relay it via XMPP. By the time I finished there wasn’t much that could be done with it other than turn it on and configure it through the control panel.