ThingSpeak - Open source data platform for the Internet of Things. ThingSpeak Features
Tuya Smart - Tuya Smart is a free to use Lifestyle Application by Tuya Inc.
The IoT Guru - the IoT cloud backend company
GREE+ - GREE+ is a home appliances management app by GREE ELECTRIC APPLIANCES inc.
dweet.io - Ridiculously simple data sharing for the Internet of Things.
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.