To support asynchronous collaboration among remote users, collaborative applications provide collaboration services and environment through virtual workspaces. In general, collaborative applications support collaboration based on desktop-based personal computers, using the features such as resource sharing or asynchronous communication among users. Unfortunately, since those applications mainly run on personal computers, they do not easily support collaborative works in various places. In this paper, we describe the development of smartphone collaborative application which provides effective collaboration facilities like resource sharing through various types of workspaces or group communication, communicating with a WebDAV-based collaboration server. The developed application provides users with high accessibility through multi-touch/touch-slide based user-interfaces in mobile environment. To support effective communication with a collaboration server, we also present a WebDAV-based collaboration library using a collaboration protocol designed to analyze easily the responses from the collaboration server.