Public displays are currently being used in a restricted context in which only small numbers of users can create and publish content. For developers, there is no easy and consistent way to share or offer their applications to a wide range of potential buyers. Likewise, display providers and users cannot browse through different kinds of applications and buy or subscribe them by using some sort of an application store. As we know from smartphones, application stores such as the Apple App Store or Google Play Store, are a great way for both developers and providers to offer applications to a wide range of interested persons. If such an application store exists for public displays, the number of applications might increase significantly and public displays might become more attractive to daily users. Within this Diploma thesis, we designed and developed an application store for public displays based to support the vision of an open display network. The application store can be used by two user groups: application developers and display owners. Application developers can distribute their applications with different kinds of billing models while display owners on the other side can use the application store to manage their displays, search and purchase applications and finally schedule purchased applications on their displays. The application store is therefore also a powerful management tool for public displays and supports different types of applications. Furthermore, the application store provides a rich set of APIs that can be used by these applications. For example, an API can be used to request information about all available public displays including detailed information such as the display location and its hardware. After developing and deploying the application store, we added within the evaluation process an initial set of ten already developed applications. The evaluation led to a number of design and implementation recommendations for public display applications that describe how these applications have to be designed in order to benefit from the open display network and the application store APIs, e.g. by using the configuration component for web-based applications and the displays API for generating localised content. In addition, we created the Dropbox Slideshow Application type and added a sample application to the application store for demonstration purposes. The second focus of the evaluation was performance testing: we showed the scalability of the application store. The overall performance increases linearly to the number of stored applications. The application store provides a common platform for content providers and display owners. By providing a rich set of APIs that can be used by third-party providers, it can enlarge lots of interesting and useful applications that will eventually make public displays more interesting for passers-by. In addition, the integrated billing model has a high potential for new business models for selling and purchasing applications and display times.