Readwise is a service that helps you compile all the various highlights and notes that you take on various ebook platforms, and then conveniently sends you an email with a few of your top highlights each day.
The point of this service is to promote better retention of one's ebooks and articles.
Readwise was the #2 Product of the Day on Product Hunt on September 6, 2018.
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Readwise
The best way to remember your ebooks & articles