Understanding what each PDF platform actually delivers — beyond marketing language — requires examining specific capabilities. This page breaks down the core and advanced features found across the four reviewed platforms: iLovePDF, Smallpdf, Adobe Acrobat, and PDFpen. Each platform has genuine strengths and meaningful limitations depending on your operating environment and workflow demands.
Core editing varies significantly. Adobe Acrobat and PDFpen support genuine text-layer editing — modifying existing content directly within the PDF structure. iLovePDF and Smallpdf offer annotation and form filling but have limited text reflow capabilities. For workflows requiring heavy structural edits, desktop-native tools hold an advantage.
All four platforms support password protection and permission restrictions. Adobe Acrobat provides the most granular control — including certificate-based encryption and rights management. PDFpen offers solid macOS-integrated security. Web-based tools process files on remote servers, which is relevant for confidential documents — review each vendor's data handling policies accordingly.
PDF-to-Word, PDF-to-Excel, image conversion, and HTML export capabilities differ across platforms. iLovePDF and Smallpdf cover common conversion paths via browser interface. Adobe Acrobat provides the widest format coverage including PDF/A archival formats. PDFpen focuses on macOS and iOS conversion workflows.
Platform availability is often the deciding factor. PDFpen is macOS and iOS only. Adobe Acrobat supports Windows and macOS. iLovePDF and Smallpdf are browser-based with desktop apps available. None of the four offer native Linux support — Linux users typically rely on open-source alternatives.