Magic Spreadsheet - Human workforce and AI plugged into your Google Spreadsheets
Spreadsheet.com - Spreadsheets that come alive as applications
Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
SheetHub - SheetHub turns your spreadsheets (either Google Sheets or Excel Online) into a REST-ful JSON API.
Rows - The spreadsheet where teams work faster
Bell+Cat - Simpler than spreadsheets