Ebook Sales & Watermarking (EPUB, MOBI and PDF)

5.0 of 5 stars(2 reviews)

Start selling ebooks

Easily upload ebooks to our repository and attach them to products. Support for standard formats: EPUB, MOBI and PDFs. Unlimited storage.

Protect with watermarks

Use watermarking, a social-DRM technique, to protect your ebooks from piracy. Each ebook is securely stamped with customer's data.

We're invisible

We strive to never get in your or your customers' way. The checkout stays unchanged, our logo is not inserted anywhere. You won't see us.

About LemonInk

You can start selling ebooks right now. And stay safe thanks to our watermarking social-DRM technique. AND: no sign up fees, no recurring payments, just pay for what you use.

Sell ebooks

We offer support for all the standard ebook formats: EPUB, MOBI and PDF. Just upload the files to our repository and attach them to a product in your Shopify store and you're done.

We'll automatically start processing orders and watermark any files that you sell. Customers will see a download link on the 'thank you' page or in the confirmation email or in order history — depends on where you paste in the code snipped we'll provide you with (with detailed instructions, don't worry).


We'll help you protect your files by generating a unique copy of your ebook for each of your customers. The ebook will have the customer's data injected in two ways:

  • visible warning informing the customer that the file is digitally signed and including the order number as well as customer's name or email,
  • series of invisible changes that are very hard to detect and even harder to remove.

This social-DRM technique works in two ways:

  • first it strongly discourages customers from sharing files as they know that the files can be traced back to them,
  • second it allows you to act when you find one of your ebooks published somewhere in the internet — you'll be able to identify the customer who's published it and make them take the file down.


We support many customization options though not all of them are available via our interface. Just contact us and we'll help you set this up in no time. Things you might want to customize include:

  • contents and appearance of the visible part of the watermark,
  • what data is included in the watermark (pick any from the following: order number, customer's name, customers email and masked customer email),
  • translation of messages displayed on the download page (currently we offer English, Spanish, French, Polish and Swedish but let us know if you need anything else).


We're big believers in respecting your and your customers' right to privacy. By default we only gather anonymized data about your orders and even if you ask us to include more detailed data in the watermark, we never use it for anything else then to apply the watermark. Period.

We don't track you or your customers.

Straight-forward pricing

You only pay for what you use. There's no storage limits or monthly subscriptions. You decide how many credits to purchase and we charge you 1 credit each time an ebook is sold.

The credit price depends on how many you purchase at once which id designed to reflect your sales volume. But if your case is special, drop us a line and we'll try to come up with something.

Media gallery


Free to install

Volume based prepaid starting at $0.25 per watermark

5.0 of 5 stars

The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.

  • 5 of 5 stars
    100% of ratings are 5 stars
  • 4 of 5 stars
    0% of ratings are 4 stars
  • 3 of 5 stars
    0% of ratings are 3 stars
  • 2 of 5 stars
    0% of ratings are 2 stars
  • 1 of 5 stars
    0% of ratings are 1 stars

Most recent reviews


Once you read through the instructions, you'll find it incredibly simple and efficient to set up. And when I have needed help with the app, their support is prompt and very helpful. Cannot recommend this app enough if you want a good watermarking app on a budget.

Yoga & Meditation shop

Works as advertised.
Had some initial issues with setup but the developers were quick to provide a solution.