The world is fast becoming increasingly digital, networked, and mobile. The use of mobile devices is a growing educational trend and determines how knowledge is taught and used when teaching and learning. This article presents the results of a comparative analysis of web and mobile educational content, which focuses on instructional issues that affect learning in a mobile context—namely, length, density, complexity, purpose, and structure. It then demonstrates that mobile content is shorter, denser, and more complex than the content of other types of educational media, and it proposes a critical assessment of how such content should be designed.