A more secure, more discreet, and also much slower pocket encryption device is a deck of cards https://en.wikipedia.org/wiki/Solitaire_(cipher) https://en.wiki

A more secure, more discreet, and also much slower pocket encryption device is a deck of cards https://en.wikipedia.org/wiki/Solitaire_(cipher) https://en.wikipedia.org/wiki/Solitaire_(cipher)