We'd wager a hefty sum that the number of nuns who've written successful novels can be counted on the fingers of one hand and an even larger one that Japan's Jakucho Setouchi is the only sister to have done so on a mobile phone.

The 86-year-old nun had something of a head start, with a career as a novelist already under her belt, but the fact that she managed to serialise the book on her own mobile website is drawing attention across the world.

Look back in time

Her magnum opus, Tomorrow's Rainbow, first started appearing in daily chunks last May as she tapped them out on her phone and, now that it's complete, is ready for the transition to a printed version.

With visitors to her site reaching 50,000 a day, publisher Starts is confident of success.

And, in a move to fend off traditionalists eager to diss the new-fangled form of fiction, Setouchi has included many elements of the thousand-year-old The Tale of Genji – one of the world's earliest novels.