Mobile Social Network Service has been broadly researched on nowadays, however few people tries to explain the essence of MSNS, which leads to no common architecture for MSNS system. Consequently, in this article we compares the Mobile Social Network Service (MSNS) with the Social Network Service (SNS) in several aspects and present a perspective on future vision of mobile social network by analyzing the differences between MSNS and SNS. Then we have also drew a conclusion that MSNS has four basic features: 1) Activity-based; 2) Mobility and Context-based; 3) Rely on mobile devices; 4) Open platform; Moreover, based on such features of MSNS, we proposed a suit of rules as the principles to design MSNS system, based on which we found that Widget/Server (W/S) should be the suitable architecture model for MSNS by comparing W/S with Browser/Server (B/S) model and Client/Server (C/S) model. As a result of this view, we introduce the conceptual future MSNS architecture-CTC-MSNS, which consists of three main elements: Mobile SNS Widget Engine (MSNSWE), Core Social Service Server Farm (CSSSF), and Activity-Based Service Server Farm (ABSSF), all of which work in an open, collaborative and loosely coupled mechanism. In this paper, the details of the three elements of CTC-MSNS and how such architecture could be implemented are also presented.