Based on our record, Okular seems to be a lot more popular than PSPDFKit. While we know about 44 links to Okular, we've tracked only 3 mentions of PSPDFKit. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
For a commercial solution check out https://pspdfkit.com/. Full disclosure, I am a Solutions Engineer for the company. I’m happy to answer any questions you have. Source: 12 months ago
Never touched it but there’s something called PSPDFKit. Source: over 1 year ago
The team at PSPDFKit, who make this app, is one of the most knowledgeable teams when it comes to PDF content that I've ever interacted with. Source: over 2 years ago
If you mean signing as in "signing with your handwritten signature", you could use Okular () which easily allows you to do that. Filling out forms also works nicely. Source: 5 months ago
I was in a similar position lately until I found Okular. Have you tried it? https://okular.kde.org/. - Source: Hacker News / 8 months ago
I would try Okular first, though, which is free and open source: https://okular.kde.org/. Source: 11 months ago
KDE's okular might be a good choice. I haven't personally used it for epub but I know it supports it. https://okular.kde.org/. - Source: Hacker News / 11 months ago
I use okular, don't think it has web export though. Source: about 1 year ago
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