Far more older adults are using mobile devices now than a decade ago. However, the applications they use continue to lag in depth (features) and breadth (diversity). Despite the large body of research on designing technology with older adults and identifying their adoption difficulties, we know little about how older users prefer to learn or troubleshoot mobile technology following an initial adoption and ownership. In this paper, we first review the existing models of technology adoption by older adults that consider learning as a factor and discuss their limitations. Then we interview older adults who use mobile technology (n = 23) and younger adults who help them (n = 17), to identify how older adults prefer to learn and troubleshoot nowadays. Our participants represent three different cultures, North American, South Asian, and Middle Eastern. Findings suggest that in addition to mobile device proficiency, older adults' technology identity---different from their attitude toward technology---determines their learning preferences. We identify two types of learning preferences: self-exploration and social learning, and two types of support, general and social. Social support plays a role in both social learning and learning by self-exploration. Finally, we propose the senior technology learning preferences model for mobile technology (STELE) to describe how different learning preferences and support types influence older adults' mobile technology acceptance and use.