Several initiatives have implemented collaborative applications for mobile settings as diverse as hospital work, wildlife, transportation, and museums. The changing nature of mobile technology has resulted in a wide variety of applications. We explored models, architectures, and applications developed in the past 13 years to categorize the types of existing software and extract a set of common core requirements that support mobile collaboration independently of the current technology. This paper provides an analysis of the domain of mobile collaborative systems including a proposal division into several domains of use, and a study of the types of systems that exist in each of them. In this way, developers can analyze their scenario of development to get an idea of the most important requirements that should be considered for development.