Aaron Pearce, maker of the HomeCam and HomePass (reviewed here) apps, has today expanded his HomeKit utility suite with HomeScan, a simple app to show the current signal strength of all the Bluetooth HomeKit accessories in your home. You can quickly identify weak spots and find a better placement for your essential smart home sensors.

A quick recap of how HomeKit accessories connect: some accessories rely on their own protocols, like Zigbee. For instance, the Philips Hue light hub talks to Hue accessories over the Zigbee protocol, connects to the home WiFi router via Ethernet, and communicates over WiFi with HomeKit clients like your iPhone or Apple TV. You also have accessories like the Koogeek socket, which directly connect to the WiFi network. As long as you have strong WiFi coverage across your rooms, you are set.

Other devices, typically battery-powered accessories, like the Elgato Eve sensors, use a Bluetooth HomeKit protocol. These connect directly to iOS devices and HomeKit hubs like Apple TV and HomePod. Bluetooth range is generally quite wide but can degrade due to thick walls or interference with appliances. If a connection is weak, it will take a while for the accessory to respond to HomeKit requests. If a device cannot connect at all, it will simply show up in the Home with a ‘No Response’ status.

There’s not really a good way to diagnose the issue using Apple’s built-in apps. HomeScan attempts to fill that gap by displaying a dashboard of the signal strength of Bluetooth accessories as you move around your home, in real time. Using HomeScan, you should be able to notice that a connection to a sensor is poor and either move it to a new location, or bring a home hub closer to it.

You can even have the app speak the number as you walk around; all the graphs updates automatically. I think a 0-100% strength meter would be a nice option versus the current dBm graphs, which are (counterintuitively) counted from negative values up to 0.

Technically, HomeScan will show connectivity strength for all nearby Bluetooth devices. It does its best guess to match what it finds with the HomeKit accessories registered to your home, but you can manually assign them if the automatic linking fails.

It’s a simple utility app that fills a niche for people with a lot of Bluetooth-based HomeKit accessories, particularly those with larger homes. You can view the readings on iPhone, iPad and even through a companion Apple Watch app. The app is a $0.99 one-time purchase; there’s an optional tip jar in the settings to support the developer further.