Sunday's London Book Fair Digital Conference was marked by an optimism about the prospects for the industry. George Lossius from Publishing Technology set the tone early on. Dedicated e-readers, he suggested, merely allowed publishers to sustain existing revenues, but mobile offered an opportunity to increase them. Not only do mobile phones have mass ownership, but – most importantly – users appear to be far more willing to pay for content on their phones than on their computers.

The use of mobile phones as reading devices has implications, though, for what and how we read. One of the conference's recurring themes was the blurring of the boundaries between books and other media. Until now, reading has tended to take place on a device entirely devoted to that purpose: a printed book or, more recently, an e-reader. As a number of speakers pointed out, though, the rise of multi-purpose devices such as the mobile phone, and now the iPad, is changing this. Readers' expectations of ebooks are increasingly informed by their knowledge of what else their device is capable of, such as playing games or audio. In this environment, an ebook that simply replicates the experience of text on a page is going to struggle for readership, while one that embraces the possibilities of the form will find it easier to justify a price point in line with that for print.

Some of the most interesting demonstrations at the conference were clearly informed by this knowledge. Kate Wilson's Nosy Crow produces applications that use the iPhone's touchscreen for games involving interactive children's stories, while Enhanced Editions' version of Nick Cave's novel Bunny Munro combines text and audiobook, synchronised so that the reader can easily resume in one format where she left off in another.

Most speakers acknowledged the challenges involved in creating such new forms of content, not least in terms of the additional costs involved. All seemed in agreement that digital should be incorporated into workflows and not treated as an add-on to print, but opinion was more divided over whether it was better to bring digital expertise in-house, partner with technologists, or hire offshore developers.

At the heart of the conference, however, was a widespread acknowledgement that what was most important of all was a renewed engagement with the reader. Whether by tracking user behaviour within ebooks, or by engaging with readers via social media, discovering the reader's needs and satisfying them would continue to be paramount.