The sudden switch to online learning at South African universities exposed how user experience (UX) and interface design can affect learner engagement, especially in mobile-first, bandwidth-constrained, and multilingual context. The research presents evidence how UX/UI features influence higher learner engagement and success using e-learning platforms. The paper also proposes a design and evaluation protocol for institutions adapted for the South African environment. In regards to methodology, a scoping review of peer-reviewed studies on e-learning UX, engagement, and completion was conducted; a thematic case synthesis of South African implementations was performed; secondary national indicators on device/connectivity access to bound design constraints were integrated. Evidence was mapped against established UX frameworks (ISO 9241-11 usability, Nielsen heuristics, WCAG 2.2 accessibility, and Universal Design for Learning). As for the findings, a logic model was presented linking specific UX patterns to measurable engagement outcomes. As a result of the research, it was revealed that four main UX determinants consistently aligned with improved engagement: Information architecture and navigation clarity, Consistency and cognitive coherence, Interactive feedback loops, Technical performance and mobile responsiveness. South African cases that adopted these patterns reported fewer support requests, higher activity completion, and more stable participation, whereas data-heavy, inconsistent designs correlated with disengagement and inequitable access. Therefore, the study provides an evidence-based South African-adapted UX Pattern Library, as well as a Monitoring & Evaluation protocol pairing SUS/UEQ surveys and short task-success tests with LMS analytics for continuous improvement. The argument is presented that UX/UI is a strategic lever for equity: when designed for mobile, bandwidth, language, and accessibility realities, platforms expand participation and reduce attrition.

Keywords: User Experience, User Interface, e-learning, Learner Engagement, Inclusivity, Online Learning, LMS, Digital Inequality.