The funny thing is that writing notes (I.e., typing text) is among the easiest things to achieve on a computer. Actually figuring out what to do with them is what requires some thought.
I say that to say, I’m interested in your app. I was late to things like Pinboard and Delicious so I never got into the whole “public online bookmarks” thing.
It's a little bit different to Pinboard and Delicious; it's private by default and you can choose to share things in public feeds if you want, but instead of sharing bookmarks in the feeds, you share text highlights (ie. the things that you found interesting about the bookmarks - this is either a text highlight from an article or a comment from HN etc. on an article)
It has some surprising other uses, too. For example, after being frustrated at how difficult it is to find story and world-building refreshers (without spoilers) when going back to a multi-novel fiction series, I have started using feeds to keep spoiler-free Kindle highlights that focus on key elements of the world, story and characters to ease me back into a series (and to share with others who might be interested in the series).
I say that to say, I’m interested in your app. I was late to things like Pinboard and Delicious so I never got into the whole “public online bookmarks” thing.