Here's a brief description of Evernote from the source:
"Use Evernote to save your ideas, things you see, and things you like. Then find them all on any computer, phone or device you use. For free."
Evernote is a note-taking, idea-saving application that has been adopted by over 3 million people. It syncs up your notes with a remote server, so accessing your latest notes on multiple devices is automatic. When you upload images, Evernote will OCR them to make them searchable. You can embed files as well, though only PDFs, .txt and images with the free version. The premium service enables a few additional features such as embedding any kind of files and increasing the amount of bandwidth allotted to you per month.
The idea behind the Evernote module is twofold. The first goal is to leverage the Evernote API to make it a blogging platform. Because Evernote is a great way to gather ideas and information, the next logical step is to make sharable information accessible on the web. See here for more background. The result of bringing Evernote and Drupal together is a rapid blogging tool that will integrate into many people's workflow.
Here's what a typical workflow would be for setting up a feed: