Evernote is a web service, designed for notetaking. A "note" can be a piece of formatted text, a photograph, a voice memo, or a handwritten "ink" note. Notes can also have file attachments.
A normal username is a without payment "Free" account with limited user rights and a limited (e.g., 60 MB) memory space.
quite widely used
Evernote data is private by default and own by author
privacy and data protection changes are informed only on the web
collection of user data
To use it requires a registration.
FAQ, community (direct support only for business customers)
Evernote Corporation, USA