When designing the hybrid OSN, there are a few limitations that need to be considered, for which appropriate solutions have to be found. These restrictions include:

\begin{itemize}
	\item \textbf{Interfaces of the OSN}: Ideally the OSN offers a public API with full functionality. Since the user's data should be protected as best as possible, access via the API is usually restricted. The restriction may be due to a limited number of requests per time interval or a limited range of offered functions.
	\item \textbf{Crawling the OSN web pages}: If there is no official API or if it is sharply restricted, the contents can theoretically also be extracted by crawling. However, this brings with it several challenges. Modern web pages load many contents asynchronously so that the initial HTML does not yet contain these contents. Furthermore, there are sophisticated mechanisms that notice crawling and lock out crawlers. Likewise, it may be difficult to add data to the OSN. For security reasons, in most cases, special tokens are sent along with each request to detect and prevent abuse and fake requests.
	\item \textbf{Development, operation and licensing costs}: Costs for the development, operation and licensing of third-party software may incurred. At best, conscious decisions lead to the avoidance of expenses.
	\item \textbf{Operating system or runtime environment}: Nowadays OSNs can be used on almost all devices; independent of their operating system. In order to achieve the same user experience, the hybrid OSN should be usable on the same platforms. Any restrictions imposed by the operating system (user and application rights, connectivity) must be taken into account during development.
	\item \textbf{Resources}: The devices running the hybrid OSN may have limited resources (storage space, processing power, Internet connection/data volume, battery). When making design decisions, it is important to plan as resource-conserving as possible and to find scalable solutions. Overall, the overhead for the hybrid extension should be as low as possible compared to the original application.
	\item \textbf{Availability of data}: The data that is exchanged securely and not via the OSN's servers must always be available. Whether a user is offline or how old the data is must not affect its availability.
\end{itemize}

While the restrictions on the hybrid client itself can be actively influenced and resolved, the restrictions on the OSN cannot be controlled. If the OSN does not provide any interfaces and the hurdle of data exchange with the servers is insurmountable, this can completely prevent the development of a hybrid client.