Tokyo-based software developer Panel Nine has now made its digital graphic novels app Sequential available in the United States and worldwide. The free iPad app, which "specializes in sophisticated digital graphic novels designed for adults from the world's leading creators," launched in May in the United Kingdom and Ireland.

The company has already partnered with U.K. publishers Blank Slate Books, Myriad Editions, Great Beast, Tabella and Knockabout, and deals with SelfMadeHero and Walker Books forthcoming. U.S. publishers are promised soon.

Among the creators featured in the digital storefront are Alan Moore, David Lloyd, Brian Bolland, Eddie Campbell, Hunt Emerson, Nicola Streeten, Darryl Cunningham, Gilbert Shelton, Nick Abadzis, Oliver East, Kevin Mutch, Hannah Eaton and Woodrow Phoenix.

"We believe that Sequential is the digital future of graphic novels and sequential art," Panel Nine CEO Russell Willis said in a statement. "We're working with the world's leading graphic novel publishers and creators to expand the market for one of the world's most under-appreciated art forms -- and rather than go the tired old commercial route with the touting of superheroes, a genre that has unwittingly tainted and held back the art form for too long, we stand for graphic novels that feature accessible, intelligent, entertaining, life-enhancing storytelling at its visual and verbal best – and haven't been designed just for geeks."