"Known" device is detected as "unknown" after some time

Thank you for this great tool. It's very easy to use. But I do have a question.

When I first scanned my home network with WiFi Guard, it successfully found and correctly identified all network devices and computers in my house. It was very clear what they were, so I marked them all as "known". Since then, they have always appeared with green dots next to their names in each subsequent scan... except for my iPhone.

After a few days, WiFi Guard detected a new device in my network. I cheeked its info, and the MAC address was matching what my iPhone was showing in its settings. But I was sure that I had already approved my iPhone. Then I checked the "All Devices" list in WiFi Guard, and yes, the original record for my iPhone was still there, as a "known" device.

I am a bit puzzled.
Why is my iPhone detected as a new unknown device.
Why does its MAC address look different?
What can I do to make my iPhone recognition permanent?

Any help will be greatly appreciated.

The issue that you have stems from the new privacy feature added to the operating systems of many different devices. This feature changes the device MAC-address to prevent tracking, but it also interferes with device recognition.

In your case, if you are using WiFi Guard in the trusted environment of your house, the best solution would be to use a "fixed" MAC-address in your iPhone for your home Wi-Fi network connection:

1. On your iPhone, open the Settings app.
2. Go to Wi-Fi section, and tap the circled "i" icon next to the name of your home Wi-Fi network. This will open your home network settings.
3. Scroll down to the Private Wi-Fi Address setting and change it to "Fixed".

Once you have done this, your iPhone will consistently use a unique private MAC-address for your home network. This consistency will allow WiFi Guard to keep recognising your iPhone in the future.

If you are interested, we also have this article that provides more information on the topic.