The publishers of the iFlow Reader ebook app have launched a stinging attack on Apple, blaming the computer giant’s controversial agency publishing model for putting it out of business.

In an angry blog post, publishers BeamItDown Software announced the death of the company and iFlow app for iPad and iPhone which it said had been caused by Apple’s insistence on taking a 30 percent cut of every book sold.

“Apple has made it completely impossible for anyone but Apple to make a profit selling contemporary ebooks on any iOS device,” the publisher writes in a blog announcing the demise of the app and the company itself. “We cannot survive selling books at a loss and so we are forced to go out of business.”

Users of iFlow Reader, launched as an iPad version only months ago, are being urged by the company to download all purchased books to their computer by May 31, or risk not being able to access them at all.

Trouble appears to have started with Apple’s recent insistence that developers sign up to an agency agreement through book publishers, which effectively forces them to sign away any profit they had previously been making on book sales to Apple itself.  

Unable to sign an agency agreement with publishers Random House without incurring losses on every sale, BeamitDown had been forced to pull 17,000 titles previously offered through that relationship.

“Five of us spent nearly a year and a half of our lives and over a million dollars in cash and sweat equity developing the iFlowReader app,” reads the blog. “We put our faith in Apple and they screwed us.”

The number of users of the app is not revealed by the company but it claims to have been connected to six million book downloads in its three years of existence.

Apple’s hefty levy on ebook sales has been widely criticised as excessive and in contrast to the lower percentage being asked by Google to sell ebooks on Android devices.