Letter puzzles
Quill & Key
Someone left you a letter.
Decode a real letter, one line at a time.
Coming soon to the App Store
How it plays
Each day brings one line of a real letter from history, written in a simple substitution code: every letter stands for another. A few letters are given to start you off. Type your guesses on the keyboard; when the line is complete it is checked for you. Every line has exactly one reading.
Finish all the lines and you can read the whole letter. Finished letters stay on your shelf to read again. No account and no internet connection needed.