The sneaky rule that only comes up when you actually hit publish on your opus – unless you're the kind of person who meticulously combs end user license agreements – states that if you charge people to buy your book, you can only sell it through Apple.
"If your Work is provided for a fee (including as part of any subscription-based product or service), you may only distribute the Work through Apple," the terms read.
You belong to Apple now
So, while the iBooks Author app is free to download, you're signing yourself out of any future publishing deals, you're cutting out anyone who reads ebooks on a Kindle or any kind of tablet other than the iPad unless you're giving your book away for free.
Dan Wineman, who first flagged the lockdown up, notes that you can actually move the document between Apple devices without going through iBookstore and they'll still open up in iBooks.
Still, it's a let down for any aspiring author thinking that at last there's an easy, cheap way to spread their work to the masses – and a bold move from Apple.
Once authors cotton on to this legal finagle, they may choose to opt instead for the less-swish-but-available-on-more-devices Kindle Direct Publishing programme, which doesn't seem to demand exclusivity unless you go opt for KDP Select (although we've asked Amazon to double check on this for us).
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Former UK News Editor for TechRadar, it was a perpetual challenge among the TechRadar staff to send Kate (Twitter, Google+) a link to something interesting on the internet that she hasn't already seen. As TechRadar's News Editor (UK), she was constantly on the hunt for top news and intriguing stories to feed your gadget lust. Kate now enjoys life as a renowned music critic – her words can be found in the i Paper, Guardian, GQ, Metro, Evening Standard and Time Out, and she's also the author of 'Amy Winehouse', a biography of the soul star.