Postman - The Collaboration Platform for API Development
Google Cloud Endpoints - Google Cloud Endpoints provides the tools to develop, deploy, protect and monitor your APIs.
DataEquity.io - DataEquity: The API Platform for API Governance
Django REST framework - Django REST framework is a toolkit for building web APIs.
WSO2 API Manager - WSO2 API Manager is a 100% open source enterprise-class solution that supports API publishing, lifecycle management, application development, access control, rate limiting and analytics in one cleanly integrated system.
Blobr - Your supercharged data analyst. Seamlessly integrate and analyze business data from multiple sources, offering deep insights into marketing performance and sales.