On the surface, the iMonitor may seem like a digital era version of print industry directory SRDS (Standard Data and Rating Service), which for decades has helped advertisers and agencies keep track of the specifications of magazines and newspapers published in print. But McPheters & Co. chief Rebecca McPheters says it is much more than that, because iMonitor doesn't simply compile who's doing what in mobile apps publishing, but also evaluates different business and publishing models, and perhaps most importantly, advertising formats, and rates which ones are working, and which ones are not.

Based on McPheters experience to date, it is a marketplace that does indeed require monitoring. When she launched her initial report two weeks ago, iMonitor was tracking 161 publication based apps. Now it is up to 214.

She says she is refreshing here database twice weekly, and that she is tracking 50 different metrics across all forms of applications-based publications: large ones and small ones, consumer and business, domestic U.S. and international ones alike.

"What we are seeing is a wide range of quality, a wide range of developers, and a wide range or publishing and pricing models," she says, adding that to date, only on common metric has emerged for comparing the results of these publications: downloads.

But even when using downloads as a metric, variation abounds. Some downloads are free. Most are paid. Some are clunky. Others work well.

"In terms of best practices, we are finding that there currently are glitches in a relatively high proportion of apps," she notes, adding that there needs to be more "rigorous testing" of publishing apps than is currently taking place in the publishing industry.

"It's not about buying pages anymore," says Robin Steinberg, senior vice president-print investment & activation director at Publicis' MediaVest unit, which is the first agency to subscribe to iMonitor. "It's about understanding these publishing brands and buying them across platforms, and understanding how the experiences differ across them."

Steinberg says MediaVest currently is buying app-based publications for "dozens" of clients, and that it is critical that the agency keep apace of the rapid changes taking place in the marketplace. She says she doesn't believe that apps will replace printed publications entirely, but that they are becoming a unique, and distinct part of the business that requires unique perspective and understanding for advertisers and agencies.

That indeed seems to be the case, according to McPheters, who says that based on iMonitor's initial findings, the wide variation of apps-based publishing models is yielding a variety of results. For one thing, she says that "navigation guides" have quickly emerged as a best practice, though not every publication uses them, and there is a range of quality among those who do.

"Navigation guides are pretty normative now, but Times of London is by far the best we've seen so far," she says, emphasizing that it is important to track overseas publications as well as domestic ones, because innovation is happening everywhere.

She says advertising models are still in flux and developing quickly, but some general rules have already begun to emerge.

"The most important thing is to focus on the user experience," she shares. "If you take [the reader] outside the app, it disrupts the user experience. We don't like [advertising formats] that take them out of the app, unless there is a very easy return path."

Another example of a potentially negative advertising format, is one in which the user is required to physically interact with an iPad or other mobile or tablet computing device.

"There are some interesting ad formats that require physical rotation of the iPad or device. But we're not big fans of something that disrupts the experience, "she notes, adding that while that might be appropriate for other kinds of apps, such as games, it is not deemed a good advertising experience.

McPheters says iMonitor will continue to grow over time, tracking publishing apps, as well as so-called "companion apps" - utilities and features within publication applications - across all of the apps-based platforms that emerge, including iPads, iPhones, tablet PCs, Kindle, Nooks and other e-reading devices.

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