Last August, two of the top 10 digital comic books in the comiXology app were written by Joshua Hale Fialkov. The first was no surprise—a blockbuster from Marvel Comics featuring some of its most popular characters. The second, however, was the debut issue of a self-published suspense title called "The Bunker."
Hale Fialkov said the launch "literally couldn't have gone better for us."
In a bricks-and-mortar comic book store, it's almost unheard of for a new independent title to crack the top 10. But digital comics are reshaping the playing field. Selling through an online storefront is helping self-publishers find new readers and reduce the cost of reaching them.
Several companies, including Amazon, offer digital comics platforms, but self-publishers say comiXology's dominant position makes it especially attractive. ComiXology is one of the highest grossing apps in the iTunes store and has exclusive deals with the likes of Marvel and DC Comics. As of September, users had downloaded more than 200 million comics.
So it was big news when the company announced last year it would take submissions from independent creators through a project called Submit. In its first year, comiXology has released more than 1,000 independent titles through Submit.
The privately-held comiXology does not release sales figures, but taken together, titles in the Submit section ranked number six in overall downloads and number 10 in gross revenue among publishers in the digital store.
"The response to Submit has been overwhelming and overwhelmingly positive," comiXology co-founder John D. Roberts said in an email. He added that the project "proves people are hungry for new content, indie content, and Submit is the perfect way to give them what they need."
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To be sure, digital sales might not turn the financial tide for many self-publishers. Creators split sales with comiXology, and app store operators such as Apple and Google typically take a 30 percent cut from mobile downloads. So creators earn about 50 or 35 cents for a digital comic priced at 99 cents.
But the project provides solutions to some problems that have historically vexed independent creators.
Distribution is one of them. Comic book stores purchase large shipments of big name titles such as "Spider-Man" because they're proven sellers and there's a market for back issues. But self-publishers must build relationships with store owners and manage their stock of printed books.
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JSB, the name used by Chicago-based comics author and founder of The Simon Corporation label, launched his mystery comic, "It Looks Back," through Submit to make it more accessible. Until recently, he sold most of his books at conventions, through his website and at local comic shops.
"Going digital has essentially expanded my potential readership from the greater Chicago area to the entire planet," said JSB. He added that he's able to sell digital comics for less because he doesn't have to worry about stock or printing.
Digital sales can also remove barriers that prevent breakout hits from reaching a wider audience.
In 2005, Entertainment Weekly gave Hale Fialkov's self-published comic "Elk's Run" a glowing review. But he had printed only 800 copies, so few who read the review would be able to find it. Now, Hale Fialkov said mobile stores help convert good press into sales by making comics immediately available.
"It's really about availability. Comics are a pop art, and they haven't gotten too far from when they were in a spinner rack at 7-Eleven. It's still an instinct buy," he said.
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The digital storefront also gives self-publishers the opportunity prove a book's viability. Following the success of "The Bunker" Oni Press optioned to print it. The first issue hit stores last month and sold out in 24 hours.
It's little wonder some independents are changing the way they do business.
Ten years ago, Drumfish Productions founder Rich Bernatovech released his first title, "Sentinels," in four volumes of about eight issues each. The strategy showed readers he could finish a storyline and helped him avoid delays between issues, a common problem for first-time self-publishers.
Bernatovech changed course and released his new title, "Neverminds," in single issues, in part to sell digital copies. He said comiXology also gives him the opportunity to find new fans for "Sentinels" without investing in printing. He plans to release the book in color for the first time through Submit.
"There's a huge market for just having a brand, a catalog," Bernatovech said. "My goal with this is to build a bigger audience, build our brand out."
As self-publishers have flocked to comiXology's Submit, there have been some bumps in the road. Several publishers said it took a few months to get their books approved and a few more until they went live.
ComiXology's Roberts said there are always challenges when asked about the delays and whether it was difficult to allocate resources to digitizing lower-selling independent books. He said the benefit of Submit is the success of better selling independent comics evens out the books that need more time to find an audience.
For now, self-publishers say delays are a small price to pay for the opportunity to reach a global audience with the swipe of an iPad. It beats fighting Spider-Man for a spot on the shelves.
UPDATED: This story was updated to reflect that ComiXology has released more than 1,000 independent titles through Submit.
—By CNBC's Tom DiChristopher. Follow him on Twitter @tdichristopher.