Chapter 3 explores children’s digital books as a powerful illustration of what well-designed EdTech can achieve when grounded in learning science. It begins by showcasing diverse examples of digital books and mapping their rapid global expansion, highlighting their growing role in early literacy. The chapter examines evidence demonstrating that digital books, when designed with research-based principles, can enhance vocabulary, comprehension, and engagement, sometimes outperforming print. Connecting this to the science of reading, it explains how features such as responsive narration, sensory supports, and adaptive scaffolding can strengthen foundational literacy skills. The chapter also emphasises the inclusive potential of digital books, offering accessible reading experiences for children with special needs and for families with limited access to print materials. It concludes by reviewing research on effective digital book design and emerging studies on children’s digital libraries, showing how carefully developed platforms can expand reading opportunities at scale.