For decades, parents have been encouraged to provide their young children with exposure to story books, primarily through parent-child reading. Such activity is known to promote some of the foundational supports that children’s transition into becoming readers. Evolving technology over the decades has influenced the way young children experience storybook reading. Today, book apps have replaced earlier technology such as the CD-ROM, and with current ubiquitous access to personal computers, tablets, smart phones, and other devices, digitized reading opportunities and uptake has skyrocketed for adults and children alike. Children’s e-book reading experiences are shaped by the affordances of evolving digital technology. Indeed, there is a dizzying array of multimedia enhancements to these books that aim to promote an interactive reading experience. Although the technological capacities of book apps are stunning, many parents, educators and researchers question the degree to which they actually benefit children’s literacy development. Our study, building on earlier evaluation tools for books on CD ROM, updated evaluative criteria appropriate for e-book evaluation. Using this tool, we systematically examined the design of currently popular e-book apps for young children (preschoolers to age eight), and examined the potential of the design of these apps to support young readers’ learning. We examined two overarching areas of research on children’s literacy development—print knowledge for supporting word reading skills and language development for supporting comprehension. We will discuss the findings about the design of children’s e-books in relation to their affordances for supporting the two key domains essential to reading success.