Google Keep Desktop OSX
Google Keep is an amazing tool for working with notes. Unfortunately, you're limited to the in-browser experience unless you use Chrome. Google Keep Desktop OSX simply wraps the Google Keep site in an app and allows you to quickly and easily access it as a separate entity outside of having to navigate through your browser tabs.
Please build from source if you are able to. Binaries can in rare instances cause wonky things on systems different than the one they were compiled on.