If you prioritize privacy and technical control, choose private-gpt. This tool excels for developers building AI applications or companies that require strict privacy for their documents, as it allows for local deployment and is open-source. However, be prepared for a steep learning curve if you lack technical expertise.
On the other hand, if your focus is on handling high volumes of PDF documents securely, opt for Stirling-PDF. Its design for high-security environments makes it suitable for businesses that process a lot of documents—though keep in mind that costs can escalate based on usage. Avoid this tool if you need robust mobile app functionality or want a completely free solution without limits.