Storybook apps as a tool for early literacy development

This thesis reports three studies examining how electronic storybooks contribute to young children’s literacy development. Study 1 shows that ‘reading’ e-books facilitates 4- to 6-year-olds’ vocabulary development and story comprehension. Video books including motion pictures and sounds/music were more effective than versions with merely static illustrations, in particular for learning new vocabulary. Interactive video books including extra-textual word meaning explanations were the best alternative to stimulate word learning. In Study 2, two methods of extra-textual vocabulary instruction were compared. Results showed that instructional formats that require children to invest more effort are more effective than formats that require less effort: multiple-choice questions were more beneficial than providing definitions. In addition to these effects in normative groups, Study 3 showed that independent e-book ‘reading’ is effective in children with severe language impairments (SLI) as well. However, background music and sounds embedded in video books interfered with word learning: e-books were only effective when the audio included the narration only. In sum, this thesis shows that media-specific design features such as video and interactivity may make ‘independent e-book reading’ a valuable tool to promote early language and literacy development.