The mobile network has been developed from 2nd Generation (2G) to Long Term Evolution (LTE) network in Korea. The purpose of this paper is to examine the key factors which affect network development, and to recognize how the mobile carriers and users perceive the rapid change of mobile technology. This study focuses on a pretest to confirm the important factors from the Focus Group Interview (FGI) to Korean Telco representatives and mobile device users. The results show that mobile device users consider devices and contents as more important factors while Korean Telco representatives pursue various strategies and priorities for network evolution. The study will contribute to recognize the differences between providers and users for introducing the new mobile network. Since this paper only describes the pretest results, further research will be conducted with in-depth interview data and statistical approaches.