Beeceptor - Unblock yourself from API dependencies, and build & integrate with APIs fast. Beeceptor helps you build a mock Rest API in a few seconds.

Greenboard - Generate beautiful static api documentation

MockServer - Easy mocking of any system you integrate with via HTTP or HTTPS.

You Need A Wiki - Create a wiki with Google Docs

Webhook.site - Instantly generate a free, unique URL and email address to test, inspect, and automate (with a visual workflow editor and scripts) incoming HTTP requests and emails.

Typora - A minimal Markdown reading & writing app.