Why Amazon bought Eero

Amazon could also use Eero to learn more about how people use internet connections in their homes.

I looked at the user terms for Google Wifi, a competing service, to see what Google uses the data for. It said it doesn’t track websites or what you do online. Instead, it gathers data “such as Wi-Fi channel, signal strength, and device types that are relevant to optimize your WiFi performance.” And it knows if you’re using Google products, such as Google search or Gmail.

If Amazon collects device type information the way Google does, it could theoretically know all of the devices that connect to the internet in your home. It would know you have two iPhones, three iPads, a Fire TV and two Amazon Echos. As appliances get internet connections, too, it would know you have a washer, a dryer, and a fridge connected to the internet. Amazon and its partners are already building products like smart microwaves that know when you run out of food so they can order more.

The more Amazon knows about what people already own, the more efficient it can be at suggesting and selling products through Amazon.com — which is still the company’s biggest business by far.