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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
Magic Spreadsheet - Human workforce and AI plugged into your Google Spreadsheets
SheetBest - Turn a Google SpreadSheet into a JSON Database API
Spreadsheet.com - Spreadsheets that come alive as applications
Dashblock - Turn any website into an API