Zoho Creator - Zoho Creator is a low-code application development platform that helps you build a custom, mobile-ready apps to run your business.
OpenXava - OpenXava is a Web Java Framework for Rapid Development of Enterprise Applications.
Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
Vaadin Framework - Vaadin is a web application framework for Rich Internet Applications (RIA).
MySQL - The world's most popular open source database
Grails - An Open Source, full stack, web application framework for the JVM