Readwise - Effortlessly rediscover and organize your Kindle highlights
Lunyr - A decentralized crowdsourced encyclopedia.
Knotes - An efficient, beautiful Kindle highlights & notes manager
Tealfeed - A knowledge sharing platform to empower creators
Newsletters to Kindle - Read your newsletters on your Kindle
BoostHQ - An online community platform for your employees to gain knowledge, share experiences and learn from each other.