AirPods are everywhere

For two years, Apple's AirPods were a bizarre curiosity. They were clever, but they looked odd and didn't sell very well. Then, they exploded, and according to one source, they have sold more units than even the iPhone at the same age.

The state of play: This will come as no surprise to anybody who has walked down the street or taken the subway in New York of late. AirPods had limited availability when they were first released, but as they became more common, they also started to look less weird. With broad adoption, Apple has managed to re-architect what is socially acceptable and even desirable.

The rise of AirPods has also followed the iPhone upgrade cycle. When people get a new iPhone without a headphone jack, that's often their impetus to buy headphones they can use across all of their devices.

• AirPods are also an elegant solution to a core problem with all smartphones, which is that they're clunky and generally hard to use as a phone.

Our thought bubble, from Axios' Courtenay Brown, who got a pair of AirPods for Christmas: "One day without AirPods taught me that I've forgotten how to talk on the phone and basically do my job without them. Ordinary bluetooth headphones — which squeeze my ears, make them sweat and are just a way less seamless experience — are not an adequate replacement."

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