It took me a while to realise what the man sitting next to me on the train was doing. He was flicking through pictures of a little girl on his phone; zooming in on some, cropping the images. Hardly unusual, of course, except that on closer inspection the pictures were very clearly of the toddler sitting opposite us, playing with her parents. On a crowded train of people mostly staring obliviously at our own phones, a stranger had been covertly photographing that little girl over and over again. And if it hadn’t been for that very visible phone screen giving him away, he wouldn’t have been caught.

That encounter was a while ago but my memory was jogged last week listening to a clip of Meta’s VP of wearables, Alex Himel, talk fondly to the BBC about using his new smartglasses to film his daughter singing in a talent contest. They let him capture the memory without having to watch her through a screen, he said, freeing him to be “kind of living in the moment, head up and hands free”. So far, so sweet. But what about the risk of creeps potentially using them to film other people’s daughters covertly, heads up and hands free? Meta’s smartglasses have a........

© The Guardian