About Shelly
Shelly takes a fundamentally different approach to smart switches: instead of replacing your existing switch, their relay modules install inside the wall box behind your dumb switch. Your existing switch stays in place and works normally — but the Shelly module gives you Wi-Fi control, local API access, energy monitoring, and full Home Assistant integration.
This approach has made Shelly the darling of the home automation community. A Shelly Plus 1PM costs $18, installs behind your existing toggle or rocker, and gives you energy monitoring, local MQTT and REST API, native Shelly integration in Home Assistant, and optional cloud access — all without touching your wall plate. For renters, for people with unusual switch styles, or for anyone who wants local control at the lowest possible price, Shelly is in a category of its own.
Shelly's firmware supports local-first operation without any cloud account. Their newer Wave series adds Z-Wave support. They've also been adding Matter to newer models. The limitation is setup complexity — configuring MQTT and integrating with Home Assistant requires more technical comfort than a standard switch.
Strengths & limitations
Strengths
- Cheapest path to local Wi-Fi control with energy monitoring
- Installs behind existing switch — no wall plate change needed
- Full local API (HTTP, MQTT, WebSockets) — no cloud required
- Native Home Assistant integration with real-time status
- Z-Wave versions available (Wave series)
- Can be flashed with open firmware for complete local control
Limitations
- Requires neutral wire (most models)
- Setup is technical — not beginner-friendly
- No Apple Home without HA bridge
- Small form factor can be tight in shallow boxes
Editorial perspective
Shelly is the best option for Home Assistant users who want maximum local control at minimum cost. The Plus 1PM is arguably the highest-value smart home product available.
