Physical books are also simply easier for younger children to use. "Real books are much easier to hold and manipulate," Ng says. "One does not have to consciously learn which button to press or where to put one's finger. Often times, parents—or children themselves—may want to turn to previous pages to understand similarities or differences between different objects or characters, or be reminded of the causes of an event in a story. It is just much easier to do that with real books."

Giles agrees: "With real books, it's easier to flick back and find something you’re looking for. There is also a more active hands on, sensory experience."

Finally, parents should consider the potential effects of more screen time on their children. Although reading is an educational activity that helps a child learn and develop their language skills, an e-reader is still a screen.

"Recent WHO [World Health Organisation] guidelines state that children under 2-years-old should not be exposed to any screens at all," Giles says. "For children aged 2 to 5, an hour or less is suggested. The guidelines are tied up with advice on sleep, physical activity and obesity—extended screen time effects all of these. The other big question is screen addiction, but it’s still an unknown as to whether the use of e-readers would contribute to that."

At the same time, Giles acknowledges that e-readers might possess added functionality that improve reading skills. "There seem to be early studies that suggest e-readers can boost early literacy skills through functions that highlight words children sound out or define words they struggle with—this can be rewarding and motivating."

And on the other hand, words on a screen are still a better option for your child than, say, videos or games. "Compared to printed words, videos are more likely to be overstimulating to kids," Ng says. "But in general, the younger children are, the less suitable e-books are for them. I would say children in pre-school and kindergarten should read real books."