- Easy to organize (directory structure, hashtag, etc.)<p>- Easy to search<p>- Markdown<p>- Vendor-free (data exportable in open formats)<p>- Comprehensive API<p>- Browser extension (think of Evernote's web clipper)<p>- Share-ability<p>- Collaboration (like Google Docs)<p>- Cross-device syncing<p>- OCR<p>- Data protection and security<p>- Open source<p>- Rich integration (with Slack, GitHub, GMail, etc.)<p>- Beautiful UI<p>- Themes<p>- ... and anything else I did not think of?
Native desktop/mobile apps that support simple formatting like markdown with an import/export function in either .json or (preferably) .md or .txt.<p>A simple tagging system (also in a simple format like .md or .html) is a nice feature. 1-2 levels of board-style organization/visualization is also useful.<p>Import/export is key - I just transferred all of my google keep notes to .md via pandoc and it was a pain. This functionality also addresses a lot of the sharing issues at a simple level - you can send or text .md files, for example, or work on them in a shared dropbox file.<p>Turtl comes very close to this for users interested in secure note-taking. Something like typora or remarkable with google-keep style organization/visualization would take care of a lot of use cases. Basically a simple markdown editor with better display/organization features. Really nailing math, table, code snippet, and image support would cover a lot of use cases.<p>Unless you really want to go hard in the paint on security, the app itself should probably focus on easy composition and attractive visualization/organization of the files.
Should be a native desktop/mobile app, lightning fast, support basic text-based formatting (e.g. markdown or simpler). Storage should be a file that can be put in Dropbox/Drive/etc for sync. And more important, free and open source.
The thing that is keeping from moving to Google Keep from Evernote is the web clipper. With Evernote I can easily clip a page (automatically removing the sidebar and other things not relevant to the article). That takes precedence over everything else that you listed.