httpbin(1) - HTTP request and response service
CoinArbitrage - Crypto Currency Price Monitor in Real time with Alerts and Notification through email, sms, Desktop Notifications Instantly and watch all of your assets and coins in one place with 16 Exchanges, 6500+ Coin (bitcoin, etherum, dogecoin,litecoin,ripple)
HTTPDump - A simple, beautiful Webhook debugging tool.
BitInfoCharts - Price, reward, difficulty, hashrate, market capitalization, block time, blocks count for all the...
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
Stampery - Stampery generates legally binding proofs of existence, integrity and ownership.