Tuya Inc.

Tuya Inc. is an IoT platform developer and provider from China. It started out with devices built on ESP8266 and ESP32 chips but switched to it's own line of chips to prevent users from installing custom firmware and by this disconnecting the devices from their (allegedly Chinese state controlled) cloud. Tuya's technology is used in many devices from cheap dollar store electronics to pricey designer lamps, their chip line is designed to be drop in pin compatible to ESP chips but using a different API. Most Tuya equipped devices nowadays can not be connected to WiFi without registering to the cloud first. It is often not visible from the product description that Tuya components are used, as customers of the platform can rebrand to the Smart Life cloud connecting app and only inspecting the chips gives it away.

Links

Tuya company website

Tuya Inc. in the English Wikipedia

LibreTiny (formerly LibreTuya) - arduino compatible open source firmware (mainly) for Tuya chips

ESPHome does incooperate LibreTiny and allows full control over supported MCU's from Realtek and Beken

Tuya Cloudcutter - A tool that disconnects Tuya IoT devices from the cloud, allowing them to run completely locally

but still incomplete list of manufactures using Tuya