This paper advocates the use of RESTful data services in mobile commerce information spaces. REST is a restriction of web services to a simple protocol centered on a limited set of access operations against data resources. This paper analyzes how REST may be used as a general design principle for mobile commerce spaces. This analysis is threefold. First, it provides an abstract component model that contains a minimal embodiment of the REST functionality needed to support mobile commerce. Second, it describes and analyzes the operation of a mobile commerce space, resulting in a reference REST-based data decomposition that may be reused across a variety of domains. Third, it provides and analyzes a set of usage cases in the mobile commerce domain, which can form the basis of future REST-oriented programming models and tools. This analysis is based on a substantial mobile commerce framework we have implemented, called Celadon. This framework is currently being used to demonstrate several ambitious mobile commerce applications.