Mobile phones are becoming a new popular platform for business applications. The number of mobile business users increases and so does the need for efficient mobile data exchange and collaboration. However, a traditional business application design approach is not suitable for mobile devices because of the limited memory and connection bandwidth. This paper presents a lightweight mobile SOA-based approach to interaction between business applications running on J2ME enabled devices such as cell phones. The paper includes position statement based on our experience and describes a prototype implementation of the architecture. The important features of our design are: using the knowledge of business processes workflow and XML compression to minimize data transferred; pro-active data push and allowing applications to fully function in a disconnected mode. The above approach results in a lightweight framework which can be used in order to develop a wide spectrum of business-oriented applications.