"A big part of learning is going from what we know and understand and making connections to the new things we're taking in. If you're not there with them, interacting with them while they're engaging with the iPad, you're not going be able to make those other kinds of connections," Booker said.
Levine said parents need to keep their hopes for apps in check.
"Just because you see a child apparently spelling by pushing a letter, that doesn't necessarily mean that they actually know how to read and spell," Levine said.
While no studies prove apps make toddlers smarter, there's no clear research that shows they hurt children.
But for parents who can't imagine shelling out $500 for an infant's toy, Levine says not to worry.
"Parents are always looking for that edge to make their child the smartest but I think the most important thing you can do as a parent is interact with your child. You don't need an iPad or a fancy tablet to make your child learn."