I purchased a book and don't always have my ipad with me if I have to have my laptop anyway. Now I find I cannot read those books on a non-iOS device. I don't understand why that is not possible in iTunes on my PC.
You did not say where you purchased it from.
If you purchased it from the Kindle Store, you can read it on your PC using Kindle for PC. You can also use Kindle for iPad, Kindle for Mac, etc.
If it is an iBook from Apple, it is restricted to on an iOS device. You can't even read it on a Mac!!!
Plan your book shopping accordingly.
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