When designing the hybrid \ac{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 \ac{OSN}}: Ideally the \ac{OSN} offers a public \ac{API} with full functionality. Since the user's data should be protected as best as possible, access via the \ac{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 \ac{OSN} web pages}: If there is no official \ac{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 \ac{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 \ac{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 \acp{OSN} can be used on almost all devices; independent of their operating system. In order to achieve the same user experience, the hybrid \ac{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 \ac{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 \ac{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 \ac{OSN} cannot be controlled. If the \ac{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.