Slicebooks offers content whole or sliced but it must be both. Slicebooks is subscription-based service that offers publishing tools. Slicebooks tools allow you to slice and then distribute your content anywhere you'd choose. Store apps,another great promotional tool. When embedded in a website, the app offers a store anywhere and the sale takes place on Slicebooks. The CMS allows on-the-spot updating.
ePub content must be tagged. ePub is the preferred format but a bookmarked PDF is also acceptable. Self-publishers can subscribe at https://www.slicebooks.com. Please note, Slicebooks tools help publishers promote their content. Slicebooks does promote via social media but leaves the marketing to the publishers, who best know their content.