Since it was completely server-hosted it was incredibly fast. You’d open it up and boom, everything all up to date. The search was fantastic. (Say what you will about Google but they’ve always been great at search. Very fast and very good results.) The site layout was clean and minimal. It was just a really good implementation. Of course they murdered it.
If you used Gmail in the early days, and ever used something before it, you probably had a moment where you said “wow, this is what email should have been all along”. Reader was the same.
https://www.youtube.com/watch?v=U_M_uvDChJQ