Smartphone usage affects the relationship between social loneliness in tourism and tourist happiness. This study discusses the effect of social loneliness on tourist happiness by considering three aspects of smartphone usage—habitual smartphone behaviors, smartphone communication, and smart tourism applications—as mediating variables. Based on stimulus–organism–response theory, this study collected data through questionnaires, analyzed the data using SPSS and Amos, and reached three findings, as follows: (1) Social loneliness affects tourist happiness either directly or indirectly. (2) Habitual smartphone behaviors not only directly affect tourist happiness but also affect tourist happiness as a mediating variable and multiple mediating variables. (3) Smartphone communication does not affect tourist happiness either directly or indirectly as a mediating variable or as one of multiple mediating variables of social loneliness. (4) Smart tourism applications not only directly affect tourist happiness but also affect tourist happiness indirectly as one of multiple mediating variables. This study is not only conducive to exploring social loneliness and the influence mechanism of social loneliness on tourist happiness, but it is also conducive to suggesting that scenic spots should add interesting group activities in project development to reduce social loneliness. Attention should also be paid to social loneliness in destination marketing.

Due to the continuous advancement of smart tourism and the improvement of tourists’ security perception of personal information (SPPI), SPPI has become an important factor affecting tourist happiness (TH). However, few studies have been conducted on the influencing mechanism via which SPPI affects TH. According to the risk perception theory and subjective wellbeing theory, the following conclusions were drawn from mixed methods research: (1) SPPI has a significant direct effect on TH; (2) SPPI has a significant indirect effect on TH through the perception of smart tourism application (PSTA); (3) the perception of smart tourism technology (PSTT) does not have a significant moderating effect between SPPI and PSTA or between PSTA and TH, but has a significant moderating effect between SPPI and TH. The discussion of this mechanism can not only promote the combined development of the two theories but also remind destinations or scenic spots to focus on improving tourists’ SPPI when developing smart tourism.