MongoDB - MongoDB (from "humongous") is a scalable, high-performance NoSQL database.

Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.

Redis - Redis is an open source in-memory data structure project implementing a distributed, in-memory key-value database with optional durability.

Zoho Creator - Zoho Creator is a low-code application development platform that helps you build a custom, mobile-ready apps to run your business.

SAP HANA - SAP HANA is an in-memory, column-oriented, relational database management system.

Ragic - World's most advanced online database engine. Build powerful online databases with simple Excel style online interface.