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Android Encrypted Notepad app with lock pattern

Dennis Lang


Encryp Notes - Features

Encryp Notes is an encrypted notepad based off of code provided by Ivan Voras (enotes).


Encryp Notes takes Ivan's app further by adding a password grid pattern UI as an alternate way to provide passwords. The grid password UI is based off of code provided by ahmed.

The grid pattern code was heavily redesigned to allow both drag drawing and tap picking. The pattern also supports overlapping paths. When a node is used multiple times, its icon rotates. When a path overlaps it changes color and reduces its width, revealing the previous path underneath.

Basic features:

Sample Grid patterns:

Start Screens

welcome.png about.png main-text.png main-menu.png edit-menu.png

Main Menu

When you start the app, you can start typing to create a document or load a previously saved document. Use the option menu to pick an action.
New document Prompt to save existing and clear screen
Open Present file browser followed by password controls.
Save Save current file with existing password, else does 'save as'
Save As Presetn file browser followed by password controls.
About Show app version and author info
File browser [experimental] open file browser to allow deletion of encrypted files
Paranoid Prevent saving of active document when no password is provided and app is closed or place in background. By default app will save current work when backgrounded and restore when app resumes. With paranoid enabled you will lose your work if you background the app and don't manually save your work.
Invert colors [experimental] Invert main screen background and font colors.

Load Document

To open and load an existing document, press the menu button and select Open... You will be presented with a file selection list of existing encrypted files. The file selection list shows the file name, its modification date and file size (# characters).

After selecting a file you need to provide a valid password to decrypt the document. You can enter a password in the lower box using the keyboard or use the numeric grid pattern. To use the grid patten either drag your finger across the numeric buttons or tap on the buttons. Your numeric sequence will appear in the password text box at the bottom. By default the grid pattern is displayed and your password is displayed. If you prefer to hide your password you can hit the check box labeled show.

open-file-list.png open-pwd1.png open-pwd2.png

Save Document

Similar to loading a document, you save by accessing the menu and selecting Save or Save As. You can either enter a file name or use the file browser to find an existing file to replaced. Use the grid pattern or text box to enter a password. If you hide your password and grid pattern you will be forced to enter the password twice.

save-as1.png save-as2.png

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Grid Password

Below is a movie showing the Grid Password behavior and how it supports overlapping paths and random click points. Notice the overlapping paths change color and shrink in width and repeating nodes rotate their icon.

Same sequence as movie showing key frames of movie.

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Reference / Links

  • Android Lock Pattern:
  • Other:

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    Blog about Android EncrypNotes