The proliferation of e-learning has intensified demand for high-quality digital learning resources, yet many digital books fail to achieve their pedagogical potential. This narrative literature review synthesizes peer-reviewed research published between 2015 and 2024 to identify evidence-based design principles that distinguish effective digital books from digitized textbooks. The synthesis of theoretical and empirical literature reveals that effective digital books are characterized by four interconnected design dimensions: instructional design foundations (clear objectives, logical sequencing, scaffolded activities), purposeful multimedia integration aligned with cognitive principles, explicit support for self-regulated learning, and attention to technological usability and accessibility. In contrast, poorly designed digital books—often mere electronic replicas of printed textbooks—frequently result in cognitive overload, navigation difficulties, and limited learner engagement. This synthesis integrates insights from Cognitive Theory of Multimedia Learning, Self-Regulated Learning theory, and constructivist perspectives to provide educators and instructional designers with actionable guidance. The paper concludes by identifying persistent implementation barriers and proposing directions for future research, including empirical validation of design principles across contexts and exploration of artificial intelligence for adaptive digital book development.
Bouzarhoun et al. (Sat,) studied this question.