Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
Sesame Database Manager - Lantica Software, LLC - Sesame, A Q&A-compatible Database Manager.
Sheety - Turn any Google sheet into an API instantly, for free. Power websites, apps, or whatever you like, all from a spreadsheet. Changes to your spreadsheet update your API in realtime. Neat
XtraBuild Designer - XtraBuild offers software development tools for database and reporting applications. No coding!
Sheetsu - Turn Google Spreadsheet into API
Sheep - Membership and events for SMEs and nonprofits