Galileo vs Sandbox: What are the differences?
Galileo: Analytics Platform for Monitoring, Visualizing and Inspecting API & Microservice Traffic. Galileo is an analytics platform for APIs that includes Realtime Logging, Request Replay, and Diff Comparisons; Sandbox: Quick and easy mock RESTful API and SOAP webservices. Quickly mock RESTful API or SOAP web-services with simple or dynamic responses, and fault injection to simulate real application behaviour.
Galileo and Sandbox can be categorized as "API" tools.
Sandbox is an open source tool with 161 GitHub stars and 28 GitHub forks. Here's a link to Sandbox's open source repository on GitHub.