Mobile augmented reality (MAR) has become a strategically significant technology within innovative marketing, connecting digital and physical touchpoints along the customer journey and reshaping how consumers interact with products prior to purchase. This chapter synthesizes empirical findings on MAR in app-based shopping through a conceptual lens, organizing insights around the stimulus-organism-response (S-O-R) framework as a core explanatory model. MAR influences consumer behavior through three interconnected mechanisms: enhanced cognitive evaluation (particularly perceived diagnosticity and decision comfort), affective activation (enjoyment, inspiration, and flow), and situational embedding (local presence and personalization). These mechanisms jointly drive behavioral outcomes including purchase intention, impulse buying, app reuse, and brand equity. The chapter further identifies key boundary conditions – product category fit, task-technology alignment, and user characteristics – that determine when MAR generates its greatest value. Drawing on 24 empirical studies published between 2019 and 2025, the synthesis concludes with actionable implications for marketing practitioners and a focused agenda for future research.