Not able to validated the license on hybrid mobile app

Which product are you using?
PDF.js Express Plus

PDF.js Express Version

Detailed description of issue
Is there a way to use PDF.js Express Plus on a mobile app? Or is it only possible with PDFTron?
We have a domain license for PDF.js Express Plus and works great on our web app, but the frontend of our mobile apps makes local requests to the native backend using a “” address, which makes it impossible for PDF.js Express Plus to valid the domain license.

Hello, I’m Ron, an automated tech support bot :robot:

While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:


Hi there!

PDF.js Express may only be used on a single web application and cannot be packaged into a mobile application (this is against our license agreement). Unfortunately your use case will not work with PDF.js Express for this reason.

You have a couple options:

  1. Try out our sister product, PDFTron WebViewer. We provide OEM licensing which is not domain locked and will work for your use case (in fact it does not call out to any servers). It has the exact same API as PDF.js Express, so switching over to it takes just a few minutes. If you are interested in this route you can contact our sales team (make sure to tell them you are an Express customer and that Logan sent you!). If you do go this route, we would be happy to discount you the cost of your Express key.

  2. We plan on releasing an OEM version of PDF.js Express in the near future. This version would also support your use case as it will not contact our servers either. We do not have a definitive timeline for this, but we should hopefully have it available by the end of the year.


Hi @Logan,

When you say that the OEM license could be available by the end of the year, do you mean 2021? If that’s right, then it’s close enough for us.
We already discussed PDFtron with the sales team, but for our use case, we just need the functionality of the Express Plus, but we’re definitely interested in the OEM license.


Yes I mean by end of 2021 (this is our goal anyways).

I will keep you posted on the status of this project.


Hi @Logan ,

Do you guys have any news about the OEM license?

Hey there!

We actually just released the OEM license a couple days ago. If you are still interested I can set up communication with you and the sales team - let me know.


Hi @Logan ,

I only asked because I didn’t see anything new on the pricing page.
Can you please connect me with them or send more info about this new license?

Thank you.


I can do both.

The OEM key is essentially the same as a standard Express key except it is not domain locked. This means it will work in any application regardless of domain name.

Please get in touch with our sales team here. I talked to them and they prefer people to fill out the form as it ensures they have the info they need and so that your request doesn’t get lost. Let them know Logan sent you!


Thanks for the assistance.

@Logan We have a similar use case. A hybrid app that we would like to distribute with PDF JS Express. How would you recommend for us to proceed further with our use case? A small difference to mention, our native apps works a bit differently - no local server but instead the static assets served directly to webview over file protocol.