httpbin(1) - HTTP request and response service
Spotify - Map shows when two people play same song at same time
HTTPDump - A simple, beautiful Webhook debugging tool.
SoundCloud - Enjoy music & follow favourite artists
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm