PDF Cabinet is a user-friendly application designed for iPhone users, focusing on seamless PDF annotation and collaboration. It offers essential features without overwhelming users with unnecessary tools, ensuring a straightforward experience. The intuitive interface allows for quick document skimming and review, particularly beneficial for larger files, making it easy to navigate through thumbnails in the sidebar.

In addition to robust annotation capabilities, PDF Cabinet supports real-time collaboration, enabling multiple users to annotate the same document simultaneously. It also facilitates sharing annotated documents with anyone, maintaining compatibility across various readers. Additional features like empty notebooks for note-taking, support for multiple document formats, and the ability to send multiple documents in a single email enhance its utility, making it a versatile tool for both personal and professional use.