The iPhone App store offers dozens of apps aimed at preschool students.

Preschool is a major market in the world of apps, with more than half of apps on the Apple and Android platforms geared toward kids 5 and under. But few of these apps are developmentally appropriate and most fail to teach in ways preschoolers need to learn.

Those are the findings of a report recently released by researchers at the School of Education at the University of California, Irvine. The researchers looked at 171 apps from the top 10 paid and free Apple and Android math and literacy apps available on Amazon and Google Play and found that few apps are designed to teach children based on research showing how children aged 3 to 5 learn. That means including clear prompts so children understand what to do, providing clear instructions and modeling and giving feedback that helps children understand why something is correct or incorrect. Many apps provided rewards like high scores as an incentive although research shows that the learning itself, and getting to new levels of an app, should be the desired reward for children.

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Although the researchers had a few positive things to say about the apps that were studied, such as the fact that touchscreen interactions were generally appropriate for preschoolers, they noted that apps currently available could be better. The researchers found that most apps did have a clear goal for children and that goal was often the same across apps. Half of the math apps focused on counting numbers or objects and one-third of the literacy apps focused on identifying letters. Nearly 19 percent of apps did not provide any instructions for children and only 25 percent provided elaborate instructions, such as asking a child a question and telling them what to touch on a screen. Fewer than 10 percent of the apps included any type of modeling by a character or by an on-screen demonstration to show children how to complete tasks. There were few differences between free or premium apps, although researchers noted that premium Apple apps offered slightly more evidence-based teaching practices.

Josh Golin, executive director of the Campaign for a Commercial-Free Childhood, a nonprofit advocacy group, said many apps have been “falsely marketed as educational” for years, even though there is no evidence that the apps actually help children learn. “Companies know if you want parents to download their apps, claiming it’s ‘educational’ is going to increase those chances,” Golin said. “Every app isn’t designed by working with developmental psychologists…they don’t understand pacing or how kids are processing at that age.”

The findings of this report come at a time when early learning advocates are also bringing attention to other forms of media for preschool-age children, including online preschool programs. Earlier this month, more than 100 early childhood experts signed a statement warning consumers that online preschool programs can be harmful to kids and go against what research shows children need from preschool programs.

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The authors of the preschool apps report note that there are some limitations to their study, including the fact that the report did not observe children using the apps or measure their learning and the report is meant to mainly be an analysis of research-supported teaching practices among apps for preschool-age children. The authors suggested that to improve preschool apps, developers should “consider what makes these preschool apps practice versus educational,” and parents who want to use apps for educational purposes should look at the features of the apps before giving them to their children.

This story about early childhood education was produced by The Hechinger Report, a nonprofit, independent news organization focused on inequality and innovation in education. Sign up for the Hechinger newsletter.