Tablet computers are so easy to use that even a 3-year-old can master them.
And that has some pediatricians and other health experts worried.
Since navigating a tablet generally doesn't require the ability to type or read, children as young as toddlers can quickly learn how to stream movies, scroll through family photos or play simple games.
That ease of use makes tablets — and smartphones — popular with busy parents who use them to pacify their kids during car rides and at other times. And many feel a little less guilty about it if they think there's educational value to the apps and games their children use.
The devices are expected to rank among the top holiday gifts for children this year. Gadgetmakers such as Samsung have introduced tablets specifically designed for kids and many manufacturers of adult tablets now include parental controls. Those products are in addition to the slew of kiddie tablets produced by electronic toy makers such as LeapFrog, Vtech and Toys "R" Us.
But some experts note there's no evidence that screen time — whether from a TV or tablet — provides any educational or developmental benefits for babies and toddlers. Yet it takes away from activities that do promote brain development, such as nonelectronic toys and adult interaction.
They also say that too much screen time has been linked to behavior problems and delayed social development in older children.
Dr. Dimitri Christakis, a pediatrician at Seattle Children's Hospital, points out that iPads have been on the market only for a little over three years, which means tablet-related research is still in its infancy.
Christakis says educational games and apps have some value if they engage a child and prompt them to interact with the device, but cautioned that if all children do is watch videos on their tablets, then it's just like watching TV, which has a limited ability to engage a child.
He also notes that parents need to be mindful of whether tablet time is replacing more important activities such as sleeping, reading or interacting with adults. He says that while the American Academy of Pediatrics recommends no more than two hours of screen time a day for kids over the age of 2, he thinks one hour is plenty.
"The single most important thing for children is time with parents and caregivers," he says. "Nothing is more important in terms of social development. If time with the tablet comes at the expense of that, that's not good."
Some experts, however, believe tablets and smartphones possess unique educational benefits.
Jill Buban, dean of the School of Education at Post University in Waterbury, Conn., says the more children absorb and understand technology before they start school, the more comfortable they'll feel when they enter a classroom for the first time.
Adam Cohen, a stay-at-home father of two from New York, says apps have been a key part of his 5-year-old son Marc's education since he was just a baby.
"He had an iPad at close to 18 months, so he was definitely one of those babies swiping away in his stroller," Cohen says. "Now it's different, but back then we were a little ostracized. Now he's reading at close to a second-grade reading level and I credit a lot of that to iPad apps."
Susan Linn, director of the Campaign for a Commercial-Free Childhood, says parents should be wary of any TV show or app that touts educational benefits for babies or toddlers, saying that scientists have yet to prove that there are any.
"The best toys are the ones that just lie there until the child transforms them," Linn said, pointing to blocks and stuffed animals as examples. "If all children do is push a button, that's not the kind of play that promotes learning."