The Wifi connected Shelly 1 relay can turn any dumb light switch in your house into a smart light switch for less than $15.
Shelly-1-x2 - The smallest Wi-Fi-operated relay switch.
Shelly 1 PM Installation Blog For a Typical Light Switch
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Shelly 1 Retrofit Home Automation Wiring
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Shelly 1 Relay Switch, WiFi Smart Home Automation, Compatible with Alexa & Google Home, iOS Android App, No Hub Required, Wireless Light Switch, DIY Remote Control Garage Door, UL Certified: : Tools
Shelly-1-x2 - The smallest Wi-Fi-operated relay switch.
Existing home - Smart Homes & Building Automation - Use Cases - Shelly
How to Make a Smart Home Test Bench - HomeTechHacker
Shelly 1 PM Relay Switch, WiFi Smart Home Automation, Compatible with Alexa & Google Home, iOS Android App, No Hub Required, Wireless Light Switch, Smart Appliances Gadgets, Non UL, 2 Pack:
Shelly 1 PM Relay Switch, WiFi Smart Home Automation, Compatible with Alexa & Google Home, iOS Android App, No Hub Required, Wireless Light Switch, Smart Appliances Gadgets, UL