In the last few years the market brought up a big variety of mobile devices with differing functionality. This development results in an increasing number of wireless subscribers and in the upcoming demand for a seamless access to information and services provided by the internet. To support arbitrary devices in a mobile environment we introduce an approach for adaptation at application level based on a partitioning model and abstract operations. Available techniques to support and improve mobile applications are integrated into a concept with generic and application specific components which adapt information according to the capabilities of mobile devices, network quality and user settings. We also describe a multimedia email application for the validation of our model. The implementation is based on mobile agents providing dynamic installation, flexible deployment and mobility support.