Readwise - Effortlessly rediscover and organize your Kindle highlights
Boreal - A Hacker News iOS app
Knotes - An efficient, beautiful Kindle highlights & notes manager
Box Piper Hacker News - Re-Imagined Hacker News for this decade.
Clippings.io - Organize the notes you make on your Kindle
HackerScroll - Read top articles from HackerNews in a clean, simple and minimal interface without ads or any other distractions.