WhatsApp Business - Communicate more efficiently with your customers
Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
StackWhats - Add the WhatsApp Live Chat to your website
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.
WATI - No-code chatbot builder for WhatsApp Business
Bubble.io - Building tech is slow and expensive. Bubble is the most powerful no-code platform for creating digital products.