Mobile Apps running on smartphones and tablets offer a new possibility to enhance the work of engineers because they provide an easy-to-use, touchscreen-based handling and can be used anytime and anywhere. Introducing mobile apps in the engineering domain is difficult because the IT environment is heterogeneous and engineering-specific challenges in the app development arise e. g., large amount of data and high security requirements. There is a need for an engineering-specific middleware to facilitate and standardize the app development. However, such a middleware does not yet exist as well as a holistic set of requirements for the development. Therefore, we propose a design method which offers a systematic procedure to develop Mobile Engineering-Application Middleware.