CipherBoB an introduction to cryptology

Have fun learning about and using some of the most important ciphers and codes used throughout history and satisfy your inner nerd in the process!

Have you ever been intrigued by secret codes and ciphers?

Have you ever wondered how messages were encrypted before computers existed?

Have you been fascinated by the story of the Enigma machine and wanted to know how it worked?

Inspired by a visit to Bletchley Park in England, home of the UK codebreakers during the 1939-1945 world war, CipherBoB lets you explore some of the most important codes and cipherers used throughout history.

Using CipherBob you can create ciphers of each type and then use these to encipher messages to send to your friends or decipher messages received from your friends and in the process learn about the ciphers you use. The app includes a brief summary of the history of each cipher type as well as step by step walk through of how each cipher works.

Ciphers currently supported by CipherBoB are:

Caesar ciphers

Learn about the cipher that Julius Caesar used for all his secret communications. With the Caesar cipher module you can:

Substitution ciphers

Learn about the natural successor to the Caesar cipher that is still used today! With the Substitution cipher module you can:

Polybius Square ciphers

Learn about what is perhaps the first fractionating cipher and the forerunner of the modern day semaphore. With the Polybius Square module you can:

Book ciphers

Learn about Book ciphers the favourite cipher of conspiracy theorists, mystery writers and movies. With the Book cipher module you can:

Morse code

Learn about Morse Code, the ubiquitous distance communication technology of the last century. With the Morse code module you can:


Learn all about the infamous Enigma machine that played a pivotal role during the 1939-1945 war. Using our Enigma machine you can:


Learn all about the Lorenz the unbreakable German cipher that played a pivotal role during the 1939-1945 war. Using our Lorenz machine you can:

Public/Private Key ciphers

Learn about the cipher technology that underpins most secure internet transactions. Using a very simple Public/Private Key implementation you will learn why these ciphers are so tough to crack. With the Public/Private Key module you can:

Once you have mastered the basics step it up a bit by challenging your friends to crack your code!

Version 4.1 now available in the App Store!

Download on the App Store

Today’s New Idea is a “not for profit” business which means all proceeds from the sale of this app go toward the development of other apps we hope users will find educational or beneficial.

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