Nearly all children 4 years old and below use tablet PCs and smartphones at home, including those from low-income families, according to new research published on Monday.

Researchers at the Einstein Medical Center surveyed the parents of 350 children between six months old to four years old from one of Philadelphia's low-income neighborhoods in 2014.

They discovered that even children from such low-income, minority communities have access to mobile media devices, suggesting that an income-based "digital divide" between rich and poor families is starting to shrink.

The parents involved in the survey said tablet PCs are the most popular mobile media device for young children. They added that kids even as young as one year olds use these devices for more than 20 minutes on daily average.

"Access to, familiarity with and skill using mobile devices are the first steps in achieving digital literacy," Dr. Matilde Irigoyen, chair of pediatrics and adolescent medicine at Einstein and one of the authors of the study, said.

Irigoyen, however, pointed out that social interaction between parents and children as well as parental guidance are still needed to help young children integrate mobile device use into family life.

In the study, as much as 97 percent of low-income households in the Philadelphia community the researchers surveyed had televisions, 83 percent of them had tablet PCs and 77 percent of them owned smartphones.

Additionally, 56 percent of these households had video game consoles, 58 percent had computers and 59 percent had access to the Internet at home.

The Einstein researchers found that older children were the ones most likely to have their own mobile devices.

Around three-quarters of young children at the age of four had their own tablet PC or smartphone, while half of them had their own television.

Only three percent of all children studied did not have access to a tablet PC or smartphone.

Irigoyen said that they were not surprised to find toddlers and infants use mobile devices as they were able to see it for themselves in their clinic daily.

She said what was surprising was the frequency with which these children used these gadgets, how many of them already had their own mobile device, how many of them could use these gadgets without assistance from grownups and how many of them engaged in multitasking while using these mobile devices.

The research team found that more than four out of 10 kids under the age of one and around 77 percent of 2-year-old kids used tablet PCs and smartphones daily to play games, watch videos or use mobile apps.

While the findings suggest that early mobile device use may provide benefits to young children as far as digital literacy goes, one expert believes these data reveal a disturbing trend in which parents might be taking advantage of technology to serve as some form of surrogate babysitter.

Dr. Danelle Fisher of Providence Saint John's Health Center argued that the parents surveyed by the Einstein researchers admitted to using tablet PCs, smartphones and other mobile media devices to keep their children quiet or entertained while in public places or as a substitute to interaction at bedtime.

Fisher added that young children need to have interactions with their parents for numerous reasons, and that the trend shown by the findings is worrisome overall.

The findings of the Einstein Medical Center study are featured in the journal Pediatrics.