Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
Datomic - The fully transactional, cloud-ready, distributed database
Ragic - World's most advanced online database engine. Build powerful online databases with simple Excel style online interface.
MarkLogic Server - MarkLogic Server is a multi-model database that has both NoSQL and trusted enterprise data management capabilities.
Zoho Creator - Zoho Creator is a low-code application development platform that helps you build a custom, mobile-ready apps to run your business.
Datahike - A durable datalog database adaptable for distribution.