DC Comics is expanding its digital storefront, putting all its monthly titles — from Batman to Superman — on sale at iTunes, Amazon's Kindle store and Barnes & Noble's Nook shop.

The move announced Wednesday appears to make DC Entertainment the first major comics publisher to make its titles available through online stores the same day they're on sale in comic shops. It also expands its digital offerings beyond the top industry digital purveyor, Comixology.

Hank Kanalz, DC Entertainment senior vice-president for digital, said the decision shows the importance of digital downloads to the company, which relaunched its universe last year under the so-called "New 52" banner.

"We've proven over the last two years that going digital has added to our business in general and going wider is the way to go," he said.

The decision to go with devices by Apple Inc., Amazon.com Inc. and Barnes & Noble Inc. reflected the fact that users of those gadgets have extensive libraries of digital files — movies, books, TV shows and, now, comics — and don't necessarily tend to jump from one device to another.

"If you devoted your library to being collected in your Kindle, now you have the option to add to your comics to that," Kanalz said. "You're going to have to commit to what platform you want to build your library in."

Goal to lure new readers

It also offers would-be readers the chance to buy single issues quickly.

"Instant gratification," Kanalz said. "We found that when certain books hit the news, we see a nice spike in digital sales."

For DC, and others, the proliferation of tablets — iPads, Kindles and Nooks — means more opportunities to lure new readers, said DC co-publisher and artist Jim Lee.

"As e-readers and tablets continue to explode in popularity, it's important for us to offer consumers convenience and choice in how they download digital comics and graphic novels and these new distribution deals with the top three e-bookstores do just that," Lee said, adding that the titles include not just DC but also its Vertigo imprint, too.

Besides Comixology, DC also sells its titles through its own DC and Vertigo apps.