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
Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
Sheet 2 Site - Generate a website from 📗 Google Sheets
MIT App Inventor - App Inventor is a cloud-based tool, which means you can create apps for phones or tablets right in your web browser.
Verifier - Weed out disposable, non-existent domains or invalid emails.
Bubble.io - Building tech is slow and expensive. Bubble is the most powerful no-code platform for creating digital products.