Christian fiction readers sure do love their e-books. Between Q1 and Q3 last year, they bought 31.7% of their titles in e-book form, according to Bowker Market Research. That puts Christian fiction among the industry’s most digitized segments. Across all publishing categories, only 21.6% of total book sales were e-books.

But digital adoption rates have slowed for this readership, which was reading 30% of its books in electronic form as recently as 2011. This has made publishers all the hungrier to innovate as they vie to build on past successes.

“Digital allows us to try different genres and formats that wouldn’t be considered feasible in print,” says Tyndale’s senior acquisitions editor for fiction Jan Stob. “The turnaround for a digital product is much quicker than for a print book, allowing us to be flexible with trends and promotional opportunities.”

Publishers see promise in Christian fiction divisions that have aggressively used freebies and deep discounts to cultivate e-reading habits among loyal fans. Retaining and adding readers, they say, means serving up more of what they want: quicker reads, lower price points, and faster delivery of new content. Since digital makes all that possible, publishers are now hustling to turn potential into profits.

Simon & Schuster’s Howard Books imprint has grown Christian fiction to 50% of its business, up from just 30% in 2011. That’s meant publishing more in romance, more in suspense—more of everything that stands a chance to strike a chord.

“We are looking for new [author] voices, and have experimented with e-only projects,” says Howard Books publisher Jonathan Merkh. “There’s a lot of testing going on to see if there is something that will move the needle to bring in more readers or buyers.”

This “both/and” approach ensures readers get more of what’s familiar and less familiar, too. The wild popularity of Amish fiction has drawn writers to the genre, such as former construction worker Dale Cramer, who’s helping Baker Publishing (Bethany/Revell) supplement runaway successes by Beverly Lewis.

Meanwhile, Baker is releasing more fantasy and suspense novels. One reason why: editors see backlist titles in these genres selling well. And managing backlist has become crucial, in part because authors expect it, but all the more so given sales results.

“It’s very easy for authors to bring their own product to market now digitally” without a publisher, says Nathan Henrion, national sales manager for digital at Baker. “To serve our authors well, we have to actively manage their entire catalogue and try to maximize their revenue across everything that they have available. That’s what’s changed the most in the mindset” of Christian fiction publishers with the rise of digital, according to Henrion.

Digital’s influence is proving to be a two-edged sword. While allowing for faster production timetables, it also speeds up cycles across the industry such that new hardcover releases face shorter and shorter windows in which to rack up strong sales before they’re off readers’ radars, according to Merkh.

To exploit the upside of faster cycles, core authors at HarperCollins Christian Publishing, where digital penetration jumped from 21% in 2011 to 40% in 2012, increasingly publish short e-only works that can later be aggregated into full-length digital and print products, according to v-p and fiction publisher Daisy Hutton. “We are also focusing on shorter content in response to consumer demand for quicker reads at a lower price point,” Hutton says.

Christian fiction readers have grown accustomed to low prices. The average e-book in the category sold for just $2.32 in 2011, as compared to $5.26 for the average general adult fiction e-book, according to Bowker.

Eager to satisfy demand for low-priced products, publishers are taking advantage of the new economics of digital publishing. Baker is experimenting with 50- and 75-page e-books, for instance, which would have been unfeasible in print formats. Tyndale is generating shorter works, too, along with titles that are in effect tested first as digital offerings. Tyndale’s Digital First program released three new romance novels in January, the busiest month for digital downloads.

Discoverability also poses dual challenges and opportunities. On the one hand, e-book releases can easily get lost in the cacophony of the Internet. Self-published titles pose more competition than in past eras, Henrion says, because they’re both more abundant and more easily discovered via online searches. Then again, Tyndale’s Jan Stob observes that some readers who’d never browse Christian fiction in a bricks-and-mortar store will sometimes snatch up books in the category after stumbling upon them online.

The rapidly changing world of digital publishing keeps publishers on their toes and alert to fresh ideas to capture and keep readers. They don’t expect the pace to slow anytime soon.