I love technology and apps. I'm constantly trying new things out, but I have my favorites and Readwise is definitely one of them. It helps you retain what you've learned from almost any form of reading. It syncs with your Kindle, Pocket, Google Play Books, and more. You can even import key thoughts from your physical books. (Here's a detailed description of Readwise)
One of the really cool features is an image generator of your highlights. This page displays some of my favorites. If you decide to sign up, use this link (Readwise Sign up) and we both get a free month!