Smartphone proliferation today, have up-scaled user adoption of Internet-based processing activities. These include (not limited to) e-learning, e-commerce, mobile-banking and others –all aimed at better performance, service delivery at improved execution speed, greater portability, flexibility and accessibility ease. Thus, necessitating growth expansion in mobile-app development across varying platforms that are poised to help users accomplish processing tasks while harnessing the benefits of the technology. Conversely, these techs have also allowed users to be constantly besieged by threats and security breaches. In lieu of residence, sensitive and proprietary –users have become bothered with smartphone exposure to possible data loss and theft –if they are to further adopt these new paradigms. With doubt in their minds, trust levels in user adoption continues to reduce. We seek to investigate social-engineered threats and attacks amongst undergraduates in Nigerian Universities. Result shows that phishing hits a higher successrate against smartphone users in Nigeria, which has decreased client’s trust level in Internet-based services