In this chapter, I discuss the impact of extended reality (XR) apps on learning and other educational outcomes and how XR is reconceptualizing some aspects of learning, learning environments, and assessment in interesting ways. The findings related to the use of XR apps in educational settings have been consistently positive despite constraints with the design structures, concerns about their potential negative effects in our relationships with one another, and other perennial issues, which range from access for all learners and costs associated with scaling XR to unproductive behavior, physical discomforts, females experiencing cybersickness with VR headsets more often than males, ethical dilemmas associated with safety and privacy, and a myriad of other concerns. The first part of this chapter provides evidence from several meta-analyses of XR apps’ effects involving large samples of typically developing learners and learners that require additional support services. The second part of the chapter explores the potential of XR apps in supporting personalized learning and how to design assessments that are appropriate in XR-mediated learning activity contexts. The third and closing part presents a design framework for deep learning with XR apps. The framework offers one way to assist the field of XR in STEM education and research to develop common or shared elements when designing and implementing XR apps for learning purposes.