Sandbox vs WSO2 API Cloud: What are the differences?
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; WSO2 API Cloud: A public hosted version of award-winning, open-source API Manager. It provides an open-source enterprise platform that helps to build, integrate, analyze and manage your APIs, applications, and Web services on-premises, in the cloud and on mobile devices.
Sandbox and WSO2 API Cloud can be primarily classified as "API" tools.
Sandbox is an open source tool with 178 GitHub stars and 37 GitHub forks. Here's a link to Sandbox's open source repository on GitHub.