Document Platform Overview

Welcome to the Avanquest PDF Web Viewer. Our JavaScript SDK Library comes in two flavors – as pre-built User Interface (UI) SDK and as a Headless SDK Library (without a UI).

Both components rely on an optimized WebAssembly module (.wasm), which can be run by any modern embedded web runtime – web browser or web application.

These two products work together to help you build powerful, fully branded document workflows - whether you need a simple in-browser / in-app viewer and editor, or a complete end-to-end automation engine.

Here we lay out why both products exist, how they differ, and when to use each one.

Why Two Products?

Modern document workflows fall into two broad categories:

• User facing interactionsViewing, annotating, signing, filling forms, reviewing documents, etc.
• Programmatic document processingGenerating PDFs, extracting data, merging files, redacting content, automating workflows, etc.

These two categories require different tools. That’s why our platform is split into:

• UI Component Library for in-browser/in-app, interactive document experiences
• Headless SDK (no UI) for programmatic document manipulation and automation

Each product can be used independently, but together they form a complete document platform.

Product 1: UI Component Library

A set of customizable, white-label UI components for building in-browser / in-app document experiences. Check out our interactive demo here: PDF Web App.

What it includes

• PDF viewing / editing
  • Text redaction
  • Image addition
  • Jump-to-page / hyperlink embedding
  • Ruler and / or Grid display
  • Page reordering
  • Page crop
• Annotation tools
  • Highlighting
  • Underlining
  • Applying Strikethrough effect
  • Free drawing, including 13 pre-drawn shapes
  • Applying sticky notes
  • Erasing text with whiteout effect
  • Applying pre-selected stamps
• Applying security settings
  • Apply password protection to prohibit document access
  • Password-protect access to specific functionality
  • Sanitizing – sensitive info removal
  • Metadata removal
• Form-filling
  • Creation of fillable text fields
  • Creation of combination boxes – drop down menus Malfunctions in Firefox
  • List boxes Malfunctions in Firefox
  • Checkmark boxes
  • Radio buttons
  • Ability to highlight fields in the PDF form light blue color standard
• Signature dialogs
  • Name of signing individual
  • Date of signing
  • Signature as full name, in one of 8 pre-selected fonts
  • Hand drawn signature
  • Uploaded signature from image file
• Search, zoom, navigation and display options
• Screenshot ability
• Document printing
• Sidebar, Toolbar components
• Powerful document manipulation tools
  • Merging
  • Compressing
  • Converting PDF to Word, Excel, PowerPoint, Image or Text
  • Optical Character Recognition (OCR)
  • Splitting a document into separate documents

When to use it

Use the UI library when your users need to see or interact with documents directly inside your web application. Your web application need not necessarily only be a web-browser - it can also be any application that embeds a modern web runtime:

• Electron App
• Progressive Web App (PWA) installed as a desktop app
• Mobile App using WebViews
• Desktop App Using WebView2 / WKWebView
• Smart TV and Console App
• In-car Infotainment System
• Kiosk and Point of Sale System

Typical use cases

• Client portals
• E-signature workflows
• Document review tools
• Insurance claim review
• Legal contract markup
• Education platforms with annotatable materials

Product 2: Headless SDK (no UI)

A programmatic API for creating, modifying, analyzing, and automating documents.

What it includes

• PDF generation
• Merging, splitting, and reorganizing pages
• Text and data extraction
• Form field manipulation
• Redaction and security
• Watermarking and stamping
• Optical Character recognition (OCR)
• Workflow automation

When to use it

Use the SDK when you need to process documents locally on a user’s device for either:

• Processing documents behind the scenes, without user interaction.
• Already have a UI and are looking for a PDF engine to do the processing in the background either on a user’s device or server-side. For example, if you have the UI that will feed the document workflow into our library. Our library will do the processing, return the result, which can then be displayed in your UI.
• Pure server-side processing (in a NodeJS environment), where no UI is needed. Only programmatic manipulation is involved.

Typical use cases

• Automated report generation
• Extracting data from forms
• Redacting sensitive information
• Creating contract packets
• Compressing or optimizing PDFs
• Integrating with backend systems (CRM, DMS, ERP)

How The Two Work Together

The UI handles the experience. The SDK handles the logic.

Why This Matters

By separating the UI and SDK, you get:

• Flexibility — use only what you need
• Customizability — brand the UI however you want
• Performance — heavy processing stays in the SDK
• Scalability — build simple viewers or full document platforms
• Future-proofing — UI and SDK evolve independently

Getting Started

• Start with the UI Library if you want to embed a viewer or interactive tools.
• Start with the SDK if you need to generate, modify, or analyze documents programmatically.
• Use both for complete document workflows.