Walmart plans to sell e-books and audiobooks, its latest effort to encroach on an area of Amazon strength. The nation's largest retailer said it has struck a deal to use Tokyo-based Rakuten Inc.'s e-reading service called Kobo to sell e-books and audio books. It will also offer e-readers in Walmart stores and online in the U.S. starting later this year. The content will be accessible through a Walmart-Kobo app on Apple and Android devices. Kobo offers nearly 6 million titles from thousands of publishers. Walmart is aiming to narrow the gap between itself and Amazon online by expanding its services and adding new items. The Bentonville, Arkansas-based retailer has long offered entertainment including streaming movies through Vudu or the digital game cards it sells in its stores.

It sees getting into the e-book business as a way to offer new choices for consumers. But Walmart is late to the game. Amazon has been selling e-books for years, and they grew in popularity with readers shortly after the company introduced the Kindle e-reader in late 2007. Amazon expanded its audiobooks content in 2008, when it acquired Audible. Apple and Barnes & Noble also sell e-books for their devices and apps. Apple apparently is stepping up its game, reportedly overhauling its e-books app with a new design and a better online book store.

"Working with Rakuten Kobo enables us to quickly and efficiently launch a full e-book and audiobook catalog on Walmart.com to provide our customers with additional choices alongside our assortment of physical books," Scott Hilton, chief revenue officer at Walmart's U.S. e-commerce division, wrote in a company blog post. Walmart declined to talk about prices for the e-books. As part of the alliance with Rakuten, Walmart will also launch a new online grocery delivery service in Japan starting in the third quarter. Walmart has operated a grocery delivery service in Japan with its stores fulfilling the orders. But Walmart officials said that a partnership will help accelerate its online grocery business.