Simplenote and Wordpress Desktop
Both by Automattic, Simplenote (https://app.simplenote.com/) is a wonderful FREE notes app that allows tagging, Markdown markup, sharing, exporting and a lot more.
It works on All devices including mobiles and syncs wonderfully. THE app to make notes and share and have on everything. Did I say it was FREE! :)
Wordpress Desktop https://apps.wordpress.com/desktop/
Wordpress (the great blogging and general CMS system) have a Desktop version (https://apps.wordpress.com/desktop/) along with mobile and other versions of their interface.
The great thing about this is that you can work offline or just have it running on your desktop all day, adding notes to posts. When you are ready you can just publish. That easy.