Shelly's Presence Gen4 is a camera-free room sensor that uses mmWave radar to tell whether people are in a space, and it is on sale now in the US.
The Verge reported the launch on Oct. 15 and says Amazon and Best Buy listings are expected soon. Shelly's US store lists the sensor at $84.99 in white and black.
What Shelly says it does
Shelly's store listing says the sensor tracks up to 10 people in 10 zones and detects presence without movement. Shelly's knowledge base adds the details:
- A 140-degree horizontal field when wall-mounted, and a 60-64 GHz radar.
- Zigbee 3.0, Wi-Fi 6, Bluetooth 5 LE and Matter over Wi-Fi.
- Power over USB-C at 5 V.
- Filters that ignore near-ground movement, small objects such as pets, and robot vacuums.
- A built-in light sensor.
The Verge says it works with Google Home, Apple Home, Alexa, SmartThings and Home Assistant.
Two numbers that do not match
Shelly's own knowledge base is inconsistent on people. It says the sensor identifies up to 10 people, yet its radar specification lists detection of "up to 6 objects (people)."
Coverage differs between sources. The Verge reports up to 650 square feet, while Shelly's knowledge base says up to 42 square meters, about 452 square feet, with an 8 by 8 meter limit on room size.
How it compares
The comparison below uses each maker's own page. As of Oct. 15, Aqara's FP2 page and FP300 page list no price.
| Sensor | Zones | People |
|---|---|---|
| Shelly Gen4 | Up to 10 | 10 or 6 |
| Aqara FP2 | Up to 30 | Up to 5 |
| Aqara FP300 | Not listed | Not listed |
Table entries come from each maker's page. As of Oct. 15, Aqara's FP300 page lists no zone or people count.
Aqara's FP2 page says the FP2 uses Wi-Fi and USB-C power, and monitors up to 40 square meters (about 430 square feet). It works with HomeKit, Alexa and Google Home without an Aqara hub. It also lists fall detection, which requires ceiling placement. As of Oct. 15, Shelly's store listing and knowledge-base page do not list fall detection.
Aqara's FP300 page describes a battery sensor, powered by two CR2450 cells, that pairs PIR with 60 GHz mmWave. It uses Thread and Zigbee, gives a 120-degree field and a 6 meter maximum range, and adds temperature and humidity sensing.
What a camera-free sensor can and cannot do
Shelly's knowledge base says the Presence Gen4 detects still people up to 3 meters away, and can show detected people on a map. It also says the sensor cannot see through walls or other solid obstructions, and cannot register movement behind it.
Why it matters
Our assessment: the Presence Gen4 packs Wi-Fi, Zigbee and Matter into one USB-powered unit, which suits Home Assistant and multi-platform homes, but it lists a third of the FP2's zones. Hold off on relying on its people count and coverage claims until Shelly's documentation agrees with itself, and compare retailer prices once Amazon and Best Buy list it.
