Apryse SDK

Judgement

What it is

Building block

What it does

Commercial SDK (formerly PDFTron) for viewing, annotating, editing, converting and signing PDFs and Office documents on web, mobile and server.

Adopt it when

Your product needs a full in-app document viewer and editor and you can pay for a commercial SDK.

Watch out

Licences are expensive and priced by quote.

Ready for

Production-ready

Runs as

Library

Built with

C++ and JavaScript

What the license allows

Closed source: you use it under the maker's terms and cannot change or resell the code.

Judged on 2026-11-03 from the maker's description and Wikipedia. The license and age lines are worked out directly.

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Other commercial document signing libraries and signing servers

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   iText DITO and pdfSign Apryse

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   Commercial

Under it

Every program, Apryse SDK included, runs on a microchip.

How compilers were built, back to punched paper tape