Based on the Integrative Model of Behavioral Prediction, this research examined the relationships between trust toward people online, sensation-seeking, smartphone use for accessing the Internet, and the intent to use dating apps to look for romance and casual sex. Survey data of heterosexual men and women (N = 257) was analyzed by structural equation modeling. The results revealed that, regarding using dating apps to seek romance, people's attitude and perceived norm were predictive of such intent. The relationships between the three personal attributes and the intent were mediated. Furthermore, sensation-seeking and smartphone use had a direct relationship with intent. Regarding using dating apps for seeking sex, people's attitude and self-efficacy were predictive of such intent. Only smartphone use was indirectly related to this intent. Both sensation-seeking and smartphone use also had direct relationships with this intent. The study concludes by discussing the theoretical implications of the model and offering practical recommendations to app companies and public health practitioners.