Amazon is currently testing a subscription service for books that it calls "Kindle Unlimited".

The Kindle Unlimited service will cost $10 per month and deliver ebooks and audiobooks to subscribers, much like Spotify does with music.

In total there will be over 600,000 titles and thousands of audiobooks to choose from. The pages showing off the new service appeared online before being quickly pulled down. But not before images were captured of the venture.

Amazon's Kindle Unlimited service has been rumoured for several months as a competitor to the likes of Scribd and Oyster.

While you'd think anyone else wouldn't stand a chance against Amazon it appears that only 638,416 titles were available, in testing at least. None of the big 5 publishers were taking part, yet. Whereas Simon & Schuster and HarperCollins are both working with Scribd and Oyster at the moment, according to gigaom who saw the site. Six other publishers were spotted taking part with Scribd and Oyster but not Amazon.

So perhaps Amazon will be reliant on the "7,351 Whispersync for Voice titles" that it appears to have lined up on the subscription service. Although with Scribd at a dollar less per month it's already going to be tough. That said perhaps Amazon is planning to lump this service into its Prime that includes fast, free delivery, plus movie and audio subscription services.

Of course this is all based on the screen shots and quick view leaked online. But with rumours for quite some time and a service like this making sense we won't be surprised if Amazon makes a Kindle Unlimited announcement soon.

amazon ‘kindle unlimited’ will be the spotify subscription service for books image 2

READ: Scribd launches e-book subscription service, unlimited books for $8.99/month