>>>There's no requirement for a writer to submit content to Apple (iTunes store) or Amazon (Kindle store).
Maybe I wasn't clear. Sure, any writer can set up a site, but then you cannot give buyers the convenience they expect with automagic downloads to a Kindle, Nook, or Kobo device. (I exclude iPad. Apple made competing eBook apps download via browser. Which is not something eInk devices can do.)
Maybe I wasn't clear. Sure, any writer can set up a site, but then you cannot give buyers the convenience they expect with automagic downloads to a Kindle, Nook, or Kobo device. (I exclude iPad. Apple made competing eBook apps download via browser. Which is not something eInk devices can do.)