Zim is an open source, cross-platform, wiki-based note-taking application designed to help users organize their notes and ideas in a structured, easy-to-access way. It features a powerful, hierarchical structure of pages and sub-pages, as well as a variety of formatting tools to make it easier to organize and keep track of notes. It also includes a WYSIWYG editor, so users can easily edit their notes in a familiar style. Zim also comes with a variety of plugins and extensions to further customize the note-taking experience. Additionally, Zim can be used to publish static websites or even manage a personal blog.
Evernote is proprietary, closed source and stores user data in unencrypted format on US servers with web access, which is terrible for privacy and security. They have been hacked in the past and are subject to US laws that force them to disclose data to authorities. They also refuse to support Linux operating systems. Their Mac and Windows clients are very different and both lag significantly after approximately 500 notes are in the database. Evernote are the past.
Complicated, not free. Zim is only open source notes.
Simplenote is much less functional than Zim (no rich text, no attachments to notes) and, although it works on mobile devices, it synchronizes your data through web servers where your information is kept unencrypted. In that sense, your information is much more vulnerable to hackers and government agencies than if you used Zim, stored the data locally and, if necessary, sync it with an end-to-end encrypted service such as Spideroak, Tresorit or Seafile (Seafile encrypts the file content, not the metadata).
Free and hassle-free. It's that simple.
If Zim isn't to your liking, CherryTree might be: open source, stores data locally, supports instant searches, interprets code blocks, and has more text editing features. The only thing it's not good at (yet) is drag-and-drop attachments. But that's in development, I hear.
Notion is also a wiki and cross-platform in the sense that it is a web application. It has some features that Zim does not have, for example. Multi-column layouts.
Android client, Markdown, built-in trello-like dashboard
The unique TW html file is incredibly simple and does not take into account the platform. The file can be opened in any browser. There TW will open, edit, etc. It works just as well on a phone. The file can be hosted / synced to DropBox or similar, so you don't even need to download / upload (in the usual sense). Very smooth interface to boot. Robust support community constantly adding add-ons.
I used it for a while. Very well written, fast and responsive app. But in 2017 the downgrade is musthave. Also, I could not export my settings in any format except HTML.
RedNotebook is a date-based diary application, and Zim is a hierarchical date-independent notebook.
Because it offers a similar solution.
Evernote
Microsoft OneNote
Simplenote
CherryTree
Standard Notes
Notion
TiddlyWiki
Turtl
TagSpaces
MediaWiki
DokuWiki
Paperwork
Tomboy
Notezilla
OpenNote
wikidPad
DEVONthink
RedNotebook
QOwnNotes
Bear
Evernote does not provide the ability to organize data to summarize/collect data. Evernote is tag-based (so it is quite "chaotic") and people looking for a more structured way to organize information, benefit from ZIM.