Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
Mailjoy - Delightfully easy direct mail marketing. A DIY direct mail tool created for marketing and growth teams. Design, mail & track personalized direct mail postcards and letters. Digital marketers use Mailjoy to send data-driven mail campaigns.
Endpoints - View and respond to requests on an HTTP endpoint
Felt for iPhone - Handwritten cards for the modern world
httpbin(1) - HTTP request and response service
NanaGram - Text your photos and we'll mail 4x6 prints to your Nana.