wikidPad has been discontinued. Similar apps include Notesnook, which is open source with a free version. Other options are Zettlr, Zim, TiddlyWiki and Trilium Notes. There's no shortage of Note-taking Tools like wikidPad, with more than 100 alternatives for Windows, Mac, Linux, Android and iPhone.
neutriNote is an all-in-one preservation of written thoughts, be those text, math (LaTeX), rich markdown, drawings, etc., in fully searchable plain text (universal UTF-8).
Safe Notes is a security project aimed at providing an encrypted, private note manager that works locally and protects notes from various threat actors.
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The digital notebook for developers, and makers. Ultra fast fuzzy search. Mouse or Keyboard only navigation. Pure markdown with auto formatting and indentation. Offline.
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FeatherNotes (by Pedram Pourang, a.k.a. Tsu Jan tsujan2000@gmail.com) is a lightweight Qt hierarchical notes-manager for Linux. It is independent of any desktop environment and has:
Record and save important information, brilliant ideas, and moments of everyday life easily and securely with SomNote.
Bangle.io is a web based WYSIWYG note taking app that reads markdown files right from your local disk.
Visual Outliner is an outliner software for Windows, and it uses OPML as native file format. It's not just another tasklist application, but a real outliner editor that can be used to write, view, modify, and maintain hierarchically arranged text.
Encryptic is an open-source note-taking application heavily focused on encryption. When you start writing, no one will know what you write except for you. We don’t know and we don’t want to know. That’s between you and your work.
Multi-platform outliner supporting text notes, hyperlinks, extensive import and export options, file attachments, printed output, note tagging, task management, spellchecking, audio notes, rich text editing, plugin and Lua scripting support, and multilingual features.
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The Guide is a two-pane outliner - a program that allows you to arrange text notes in a tree-like structure. It supports formatted text, exporting to RTF and hyperlinks (both internal and external).
Inquisite is a note-taking site that makes creating, searching, organizing, and importing/exporting simple and easy
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