Joplin is an interesting application to take notes quite complete and that has synchronization options. It is available for Windows, Linux, macOS, iOS and Android, and is also completely free and open source.
It works similar to Evernote, so it’s a good replacement for which you do not have to pay anything. Joplin lets you organize your notes in “notebooks” and each notebook can contain as many notes as you want.
The app has integrated search , that is, you can search according to the name of the notebooks, or the notes, or what is written or attached to them. You can edit your notes, add labels, modify the content from a text editor or from the same app.
Another good feature is that Joplin supports MarkDown, so you can write using this markup language or paste your notes already written in MarkDown into another text editor.
You have several types of views, and the most complete one shows you a preview of the text format, which also makes it a good MarkDown text editor if you want to use it as such.
Joplin also offer synchronization features through Microsoft OneDrive (they plan to add support for Dropbox and NextCloud soon), you can connect your account and keep your notebooks and notes in the cloud through all the devices where you use Joplin.
If you use Evernote you can follow these instructions to import your notes correctly with everything and format. Joplin also plans to add end-to-end encryption and a dark theme for the desktop application. Although the app is in development, it has already left the beta phase so it is perfectly stable to use every day.