Bluetooth

Bluetooth Low Energy (BLE) is built into nearly every phone, tablet, and modern hub, which makes it an easy way to pair and configure a device up close. In the smart home it shows up two ways: as the setup channel for Wi-Fi devices, and as the primary link for tiny battery sensors that broadcast readings to a nearby gateway.

Strengths

• Very low power so coin-cell and rechargeable sensors run for months or years between changes.
• Fast local pairing from a phone or hub that is already in range, with no account required.
• Local control because BLE traffic stays on-site; a gateway relays it to Home Assistant without a cloud round trip.

Trade-offs

• Short range. BLE reaches a room or two, not a whole house, so coverage depends on gateways.
• Gateway needed for many devices. Battery BLE sensors that broadcast BTHome data rely on a Bluetooth proxy or a mains-powered device acting as a gateway to bridge them to the network.
• Lower throughput than Wi-Fi, which suits small sensor updates rather than high-data devices.

When Bluetooth makes sense

Selora installations use Bluetooth for low-power sensors placed near a gateway, and for fast setup of Wi-Fi devices. Shelly’s Gen3 and Plus models pair over Bluetooth and can also act as Bluetooth proxies, extending coverage for nearby BLE sensors while still running locally over the native Shelly integration. For sensors that must cover a large area, a mesh protocol such as Zigbee, Z-Wave, or Thread is usually the better fit.