Software development is usually performed with reference to some specific computational platform for reducing the coding effort by exploiting a rich set of pre-built mechanisms. However, each platform injects into the design space its own concepts and architectural constraints that are not reflected into the programming language. Current Eclipse tools allow users to express platform-related concepts in some custom architecture-oriented and model-based language; moreover model-driven development based on meta-models can easily lead to custom IDEs, able to automatize a relevant part of software production. This is discussed here with reference to the Android platform, and the XText technology. Our experience shows that a design based on custom languages can give a great contribute in the field of software development, and can also promote the evolution toward platform-independent languages and design.