Readwise - Effortlessly rediscover and organize your Kindle highlights
HackerWeb - A simple and readable Hacker News app
Knotes - An efficient, beautiful Kindle highlights & notes manager
HackerScroll - Read top articles from HackerNews in a clean, simple and minimal interface without ads or any other distractions.
Clippings.io - Organize the notes you make on your Kindle
HNwatcher - Track keywords and users on Hacker News