ReadMe on Intercom - Let your users search your API docs from the Intercom widget
Mocklets - A HTTP-based API simulator to assist parallel development 🛠️
PublicAPIs - Explore the largest API directory in the galaxy
API List - A collective list of APIs. Build something.
Yappes - Build, manage and distribute your APIs in one place 🛠️
Airbnb Official API - Develop your application for millions of travelers & hosts