Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
SpreadSimple - A blazing-fast way to create and manage sites using Google Spreadsheets
Retool - Build custom internal tools in minutes.
Algo by AirDev - Turn a Google Sheet model into a web app in 5 minutes
SeaTable - SeaTable is an innovative no-code platform for creating custom digital solutions without programming. Intuitively build user-defined databases, applications, and workflows.
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