As the video shows, the child becomes increasingly distressed as she tries to capture her mother’s attention.

“Parents don’t have to be exquisitely present at all times, but there needs to a balance and parents need to be responsive and sensitive to a child’s verbal or nonverbal expressions of an emotional need,” says Radesky.

***

Although we are still in the early days of understanding the impact that mobile computers are having on young children, the key piece of advice from the child experts I spoke to was to make sure that device use is just one part of a rich diet of activities, particularly for under-threes, who seem to struggle to learn from screens.

Interactive, creative touchscreen experiences should be preferred over passive TV-like viewing. Parents should take educational claims from app developers with a hefty pinch of salt.

Where possible, a device should be used as a tool to enhance interactions with the child, whether that’s as a launchpad for discussion (“What’s the cow doing over there?” “What sound does the duck make?”) or as a way to inspire educational conversations that spill into the rest of the day, as appears to happen with BedTime Math.

Tronick’s still face experiment did not involve screens, but a number of researchers have cited it as evidence that parents shouldn’t be distracted by their smartphones when they are around their babies. This is true to an extent, but Tronick himself underplays its significance. “It’s all a bit exaggerated,” he says, adding that most children do plenty of activities every day that don’t involve screens.

He is concerned that the worries about kids’ use of screens is born out of an “oppressive ideology that demands that parents should always be interacting with their child.”

“It’s based on a somewhat fantasized, very white, very upper-middle-class ideology–tiger moms and helicopter parents–that says if you’re failing to expose your child to 30,000 words you are neglecting them.” Tronick believes that just because a child isn’t learning from the screen doesn’t mean there’s no value to it–particularly if it gives parents time to have a shower, do housework or simply have a break from their child.

“Many parents, particularly low-income parents, are horrifically stressed and concerned they don’t get the support they need and find parenting really lonely. Those are the big problems,” he says.

Parents can get a lot out of using their devices to speak to a friend or get some work out of the way. This can make them feel happier, which lets them be more available to their child the rest of the time. For Sandy, this is a relief to hear. “Sometimes I’m at the end of my tether,” she says, adding that she shouldn’t have to feel guilty about giving her child the iPad so she can have some “me time.” With some parents, there’s a lot of snobbery about screen use, she says.

“As a mum, I put my 18-month-old in front of an HBO baby poetry video,” says Radesky. “It’s cute and calm and I can wash the dishes or do something that’s a reset for me. That’s a benefit, but it’s something parents need to be very honest about. The video is not educating my 18-month-old. It’s a break for me as a parent.”

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