VioletNote

This is a notepad application having the encryption function. This treats plain text without decorations and saves it as a file. When changing setting, it displays the result of Markdown syntax. It can create and send the encrypted note including images.

This supports two cipher text file types ([.chi] and [.vnlt]), and the clear text file type [.txt].

Each file can be encrypted, sent, and decrypted individually.

The file type [.chi] is the Blowfish encryption compatible with Tombo and Kumagusu. The file type [.chs] is not supported.

The file type [.vlnt] is the Base64 encoding after the AES encryption. The help document includes the source code of encryption and decryption.

The text is stored as files in the app-specific storage which is invisible from outside.

The text also can be stored in the shared storage which is visible from outside.

Default character set is UTF-8. The type [.chi] supports UTF-8, Shift_JIS, and UTF-16LE. The type [.txt] supports more character sets.

The character set can be detected automatically at reading a file (It is not perfect. If failed, disable the detection in settings).

This has the viewer mode and the editor mode. The text is un-editable in the viewer mode and is editable in the editor mode.

This has the text search function (upward / downward) in the viewer mode and the editor mode.

This has the text replace function (all at once / one by one) in the editor mode.

In the search and replace functions, regular expression (RegEx) and case-sensitive can be selectable.

This has undo and redo functions in the editor mode.

When closing the editor mode, save and discard can be selectable.

This supports many functions for files in the app-specific storage (copy, delete, rename, share, make-folder, export, import, backup and restore) in the filer mode (This does not include functions for the shared storage. Use other application such as 'Files by Google' ).

This can sort the file list by file name, file size, update time, and file type.

The deleted files are held in the trash can and are deleted automatically after specified period (default 30 days). The deleted files can be put back.

To avoid repeated input, the encryption password is held in the application during a specified time (default 3 minutes).

Though default is plain text, but the Markdown or HTML interpretation result is shown in the viewer mode, when the setting is changed.

In Markdown mode, encrypted notes including images can be created and sent to somewhere else.

From text long-touch, 'Adjust Range', 'Scripts', and 'Transliterate'(from Android 10) can be called.