Developing educational apps that cover a wide range of learning contexts and languages is a challenging task. In this paper, we introduce the AppComposer Web app to address this issue. The AppComposer aims at empowering teachers to easily translate and adapt existing apps that fit their educational contexts. Developers do not need to provide extensive translations and configurations of their apps and can simply follow certain guidelines to make their apps translatable and adaptable by the AppComposer. Since the AppComposer makes use of the standard internationalization specification used by OpenSocial, even external apps can be translated without contacting the original developer.