"As a photojournalist who travels extensively around the world, home for me has always been a shifting term, with shifting people and shifting objects vying for my attention," writes Ed Kashi to present his latest book, Photojournalisms. "Upon meeting Julie Winokur in 1992, that dynamic was forever altered. When we married in 1994, a pattern of recording journals addressed to Julie was already firmly established. In keeping with the changing times, what began as paper journals was replaced with daily emails by 2000. Encompassing nearly 20 years, this book is a selection of these journal entries from various locations around the world, written for my wife."

The book was first released in October 2011, but in June this year, Kashi introduced an iPad version of Photojournalisms. The goal, says Kashi, was to create a deeper experience for "readers" by using his audio and video commentaries. "These can bring you deeper into the logistics and mindset of the stories I wrote home about. You heard my own voice talking about the details behind the photographs on the page."

He adds: "Something the app also provided, which the printed book could not provide, was a way to navigate through the book via either a yearly timeline or a map view of the places I had been. If one is curious to know what I shot in Iraq, or what I was doing in 1991, with one click you are there."

In the end, the app also gave Kashi "a vehicle to bring a more intimate look into my world. After all, this book and the app are an intimate and candid view into my process, life and the balancing act of being a traveling photojournalist while trying to raise a family."

To create the app, Kashi brought together his studio manager, Kristin Reimer, with a team of designers, video experts and developers that included Michael Curry, Phyllis Dooney, Marjorie Steffe, Jessey Dearing, Marshall Leaman and Elissa Pellegrino. "We worked in co-operation with David Gross of Mimetic Books, who offered to produce the app for a nominal fee," Kashi tells BJP. "It was a kind of barter in a way, where he would give me an incredibly good deal in exchange for the experience and association with me and my work."

The creative process was divided into three steps, starting with the app's conceptualisation and design. "We based ourselves on elements we felt worked and didn't work in other apps we saw," says Kashi. "We began to develop themes and interactive elements we felt would enhance the material. We also began to formulate graphics and the overall look: would the overall look follow the simple design of the printed book, or would we use this as an opportunity for departure?" In the end, Kashi's team decided to mimic the book's basic design to create the app's backbone, "but we used it as a departure point to add more content components", he says.

These components needed to be created, though. "We recorded audio of each journal entry from the printed version," says Kashi. "And we also recorded extra audio of me speaking about each entry, providing a more personal account of the work, in addition to the journal entries found in the printed version." The team also created a video biography and selected a wider range of images – some of which had never been published before.

"All of this required constant back and forth communication between Reimer and Gross, and since I was traveling often, I would get involved from the field to be sure the initial vision of the project was coming to fruition."

In total, Kashi spent $900 developing the app, a price tag that didn't take into account labour costs. "If one were to add up the time spent with the hard costs, maybe the out-of-pocket expenses would be between $3000 and $5000," he says.

But releasing an app is just half the work. To make it successful, its creators must also create buzz for it. "We used our own social media network presence for promotion," says Kashi, referring to his studio's newsletter and website, as well as Twitter and Facebook. "We also sent personalised email messages to bloggers and reviewers in the field. Often our messages included a promotional three-month code to unlock the app and view it." VII Photo, Kashi's agency, also helped promote the app.

But, says Kashi, one of the most important pieces of marketing involved what he calls 'Ask Ed'. "On a regular basis, I receive email questions from photography students and aspiring photographers," he tells BJP. "Commonly, these questions pertain to how to become a photojournalist, or how to balance life, what path should be taken to attain this career. Often they just wish to receive critiques of their work. Due to the amount of similar requests of this nature, we felt we should target marketing to photographic educational outlets. We reached out to a number of teachers in the field to introduce the app. We searched for blogs and people tweeting about educational aspects of photojournalism. And we created a special section of the app called ‘Ask Ed'. This section pointed the viewer to an online site that was a compilation of questions asked over the years by students and aspiring professionals. We categorised them by subject (stories, tools, personal, work)." And this site, which is hidden, can only be access via the app.

"We intended for Ask Ed to become an interactive forum, where students could engage me and have questions answered," adds Kashi. "We felt the opportunity for a direct link to speak to me and receive feedback on your career was well worth the price of the app."

Yet despite all these marketing efforts, the app has so far failed to garner momentum on Apple's crowded App Store. "Honestly, the app has not done as well as we had hoped," he reveals. "We've recovered roughly $250 of the money spent so far, and about 100 copies have been sold from June to mid-August."

The real value was promotional, he adds. "We received many strong reviews from outlets such as The New York Times, Pro Photo Daily, The Guardian, GUP and ABC News, among others. It's a great portfolio piece and a learning experience. It kept me current with the market and involved with the latest technology."

Knowing what he knows now, Kashi would probably have done things differently. "We would have streamlined the production, for example. It took far too long to create this app. We chose to go in a direction that saved us cash, but in hindsight, putting in the hours totalled on the project, we might have been better off hiring a designer and not becoming as involved as we were."

And while he doesn't have any regrets – "we learned so much and love creating new stuff"  – Kashi isn't sure he would embark on such a venture once more. "It was, once again, another exercise in dancing with the latest opportunity, only to find it brings in no revenue," he tells BJP. "This course is unsustainable."

For more about Photojournalisms and to download the app, visit Apple's App Store.