The Android OS has a function - calling the keyboard, directly in the game. In order to do this, you need to use the "Smart Office 2" program. It can be downloaded from Google Play. Next, you should open the game, and then minimize through the "home" button. Open the above program and create a "new document", and select the document format, for example DOC. At the bottom of the display, select the button called "Edit". After you do this, the keyboard should appear. Then it remains to open the game and enter the secret code.
To return to the game, you need to press the "home" button.