wdr unity multitouch app stone steps into nothingness

App 39 - Interactive Radio Play

  • App
  • Unity3D
  • iOS
  • Android
  • 3D Audio

WDR is the prominent regional broadcasting agency in the German state of North Rhine-Westphalia. It is based in Cologne, and stands for innovative media, as evidenced by the agency's crossmedia campaigns. One such campaign was technically conceptualized and implemented by redPlant in cooperation with Dear Reality. In the interactive 3D audio play application "39 Stufen" (39 Steps), the listener can get involved in the plot not just auditively but also visually and interactively.

Dive into History

The special feature of App 39 was the unique combination of an audio play with the additional interactivity of a game. The challenge was finding the proper balance, because the interaction should not detract from the actual plot. Rather, it was intended to stir the listeners' imagination and draw them deeper into the story.

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Parallel to the application, the story about Richard Hannay aired on German radio in two parts of about 50 minutes each. The individual chapters in the application were released analogously to the broadcast. The truth behind the story, however, was only revealed in the interactive audio play application. This connection of radio and mobile application was another novelty of this project.

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User Interface

The entire User Interface was conceived in cooperation with Dear Reality and technically implemented by redPlant. It was very important that menus and interaction elements were intuitive and simple, so the listener would not be distracted from the story.

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For managing the various chapters of the story, a Content Management System (redCMS) was developed and implemented as a central extension of the Unity3D editor. Apart from managing the multimedia content (audio, images, animations), it also contains a template mechanism by which new chapters could be generated from abstract base scenes. Without redCMS it would have been impossible to generate the over 100 scenes of the audio play within the tight schedule.

In this collaboration, redPlant took care of the entire software development of the audio play application, the creation and integration of visual content, as well as the integration of the 3D Audio Engine (Dear API) provided by Dear Reality. Aside from planning, design, and implementation of the application architecture, we also implemented all interaction techniques, graphic effects, and the User Interface (UI) according to the conceptual requirements of Dear Reality.


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The entire application was implemented with Unity3D.

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Android App

The Application was published in the Android Play Store.

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iOS App

The Application was published in the iOS App Store.

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The Application supports Multitouch gestures.

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3D Audio

Particularly deep Immersion with 3D audio.

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Various extensions of the Unity3D editor for comprehensive content management.