Mobile phones have become as powerful as any desktop computer in terms of applications they can run. However, the software development does not take advantage of the whole potential of mobile devices. Enterprises are now adopting mobile technologies for numerous applications. A current problem is the modernization of useful legacy systems to mobile platforms. In this context, we describe a reengineering process that integrates traditional reverse engineering techniques with Model Driven Development (MDD), MDA (Model Driven Architecture) in particular. We describe a case study that shows how to move CRM (Customer Relationship Management) applications from desktop to mobile platforms. We validated our approach by using the open source application platform Eclipse, EMF (Eclipse Modeling Framework), EMP (Eclipse Modeling Project) and the Android platform.