With the proof of concept, the basic feasibility of the idea of an extension of an established \ac{OSN} by a secure data exchange should be proven. Within the framework of this thesis, the task was to provide the proof of concept as a native Android app. Concerning the architecture, the focus from the beginning was on a \ac{P2P} solution. For this reason, a solution with additional servers was not pursued further in the creation process of the prototype. Furthermore, an interface should be available for the service provider of the \ac{OSN}, through which anonymized information can be obtained from the privately exchanged data.

With the decision for a client app, the creation of an add-on, which was discussed in the previous chapter as a possible solution strategy, was thus fundamentally ruled out. Nevertheless, consideration always included how the architecture could be this open and flexible to enable all kinds of extensions and clients participating in the \ac{P2P} network.

Since it is only a proof of concept, the mapping of the complete functionality of the \ac{OSN} was not the highest priority. However, again, this was taken into account by considerations and decisions, for example how data formats can be arranged so flexible that every function can be mapped.

Also, the focus was on compliance with the quality goals and implementation of the functional and non-functional requirements as defined in the previous chapter. How well this has been achieved will be evaluated in the following chapter for evaluation and discussion.