This page presents a concept and implementation of a prototype search application (PROSA) that enables creating own search applications using the OpenWebSearch.eu index. The concept consists of the integration of an index partition exported from the Open Web Index and a search service that builds on Apache Lucene and offers a REST API, which makes the index searchable. A prototype implementation has been created that applies the conceptual design and provides two demonstration applications. Concept and implementation should enable and encourage developers to create their own special-purpose search application.