| addViewing | | | | |
| Max zoom factor (image depth / quality) | | 1,000% | +100,000% | +100,000% | |
| Crisp graphics at high zoom | | | check | check | |
| addAnnotations | | | | |
| Collaborate in real-time | | | | check | |
| Freehand, free text, shape, comment annotations | | | | check | |
| Stamp document with text, images | | | | check | |
| Watermark to prevent distribution | | | | check | |
| User roles and permissions (control access to each annotation) | | | | check | |
| Annotation events to trigger custom functionality | | | | check | |
| Create custom annotations | | | | check | |
| Cloudy annotations | | | | check | |
| Measurement tools (distance, perimeter, area) | | | | check | |
| addModern UI | | | | |
| Modern UI written in ReactJS | | | check | check | |
| Fully responsive | | | check | check | |
| Customizable | | check | check | check | |
| Dark theme | | check | check | check | |
| Hide/Show Download/Print and other tools | | check | check | check | |
| Open source UI (source code downloadable) | | check | check | check | |
| addPDF Forms | | | | |
| User form filling | | | | check | |
| Merging form data | | | | check | |
| Programmatically prepopulate forms | | | | check | |
| Extract forms data and save values separately | | | | check | |
| JavaScript field validation/formatting | | | | check | |
| Customize form appearance | | | | check | |
| Print entered field values | | | | check | |
| Form actions/interaction between elements | | | | check | |
| addSignatures | | | | |
| Sign by using hand-drawn annotation | | | | check | |
| Save signatures for signing multiple pages | | | | check | |
| addSearch | | | | |
| Wildcard search option | | | check | check | |
| Ambient string, return context to your search | | | check | check | |
| More accurate text search | | | check | check | |
| addSupport | | | | |
| Rendering engine | | PDF.js open-source community | PDF.js open-source community | PDF.js open-source community | |
| PDF Viewer UI | | PDF.js open-source community | 1-on-1 support via forum | 1-on-1 support via forum | |
| addDocumentation | | | | |
| Guides | | | check | check | |
| Samples | | | check | check | |
| | | |