When comparing nvALT vs Quiver, the Slant community recommends nvALT for most people. In the question“What are the best Markdown editors for OS X?” nvALT is ranked 10th while Quiver is ranked 16th. The most important reason people chose nvALT is:
nvALT has a simple text box at the top (similar to that of a web browser) and when you start typing inside it, nvALT immediately displays a drop-down box of all the notes that contain the text you are searching for. The more you type, the more the search is narrowed down.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Powerful search syntax
nvALT has a simple text box at the top (similar to that of a web browser) and when you start typing inside it, nvALT immediately displays a drop-down box of all the notes that contain the text you are searching for. The more you type, the more the search is narrowed down.
Pro Lightweight
Pro Free

Pro MultiMarkdown 3 support
Has built-in support for MultiMarkdown 3.
Pro Powerful note-taking features
nvALT is not only used for simple text editing but also as a powerful tool for taking notes, TODOs, phone numbers and every other piece of information that can be stored in a plain-text file.
This is because nvALT is not designed only as a tool to write text, but also as a powerful search and organize tool for plain-text files.
Pro Right to Left support
Pro Has more features than just a simple Markdown editor
Quiver is a notebook and note-taking app akin to Evernote which happens to also be able to edit Markdown files. As such, it has a lot of useful features such as: image support, file attachments, web content support and more.
Pro Supports code highlighting
Has syntax highlighting for more than 120 programming languages.
Pro Notes can be linked to each-other
Quiver notes have unique links that can be copied and pasted into other notes to gain quick access between them.
Pro Live preview
Quiver has live preview for both Markdown and LaTeX. This helps users to better understand the way they are formatting their files.
Pro Cloud syncing
Dropbox, iCloud Drive, Google Drive, or any other file-based cloud services.

Pro Supports vi keybindings
For people used to vi keybindings, Quiver can be set up to work with them.
Pro Combination of different types of writing in one note
The most outstanding thing for me. Use HTML line breaks while writing MD text.
Also, unlike most hybrid editors like Bear, it supports instant image sizing and respective preview.
Cons
Con Not very powerful as far as text editing goes
nvALT's strength is its search feature. It has some basic text-editing features such as cut, paste, find-and-replace and so on. But it doesn't have any advanced text manipulation features available in other editors.
Con You can't edit specific files, they must be in your notebook
Con No iOS apps for editing, only a viewer available
I'd LOVE to edit and create quiver notes on my iPad!
Con The line in focus shows a border around it which is distracting
The line in focus in the editor shows a rounded rectangular border around it, which is unappealing and distracting.
Con Much more than a simple Markdown editor
Since it's more like a note-taking app (and a note-taking app built for developers) than a Markdown editor, it may be a little excessive to use it only for its Markdown editing features.
