Reviews of Amazon's iPhone application have turned more negative since the launch of iOS 7, underscoring the challenges that Apple's latest update to its operating system presents marketers as they shift to more gesture-based apps.

While the volume of app reviews for Amazon has increased since the launch of iOS 7, the average number of star ratings of the Amazon app has dropped, according to exclusive data pulled by appnique for Mobile Marketer. Before the update rolled out, Amazon generated about five reviews per day and now rakes in roughly 12 reviews.

"It tells you that with the update for iOS 7, people didn't like the change - it's a change in sentiment from postive to negative," said Jai Jaisimha, CEO/founder of appnique, Kenmore, WA.

?Marketers will have to look at apps and fix specific issues now that iOS 7 has come out,? he said.

?For marketers, reviews represent sentiment, and the reason that they need to worry about sentiment is that it drops the ranking of the app."

Retail change
Appnique pulled data from five retailers? iPhone apps ? Amazon, eBay, Walmart, Target and Macy?s ? that examine the difference in rating volume and star ranking since iOS 7 launched on Sept. 18.

The data is collected by Appnique directly from the App Store.

EBay?s app has experienced the reverse effect that Amazon's did since iOS 7 launched.

According to appnique?s data, the number of user reviews for eBay?s app decreased as a result of iOS 7.

Before iOS 7, eBay?s app brought in anywhere from 50 ? 100 reviews per day. Now, eBay?s app brings in an average of 75 ? 25 reviews per day.

Even though eBay?s app is getting reviewed less, negative reviews make up a smaller proportion of reviews than it did previously.

Target?s app has a similar pattern to eBay. Appnique?s data shows a roller coaster of the average number of daily app reviews, which Mr. Jaisimha claims is connected to promotional efforts that Target uses to drive app downloads.

The number of daily app reviews has decreased for Target since iOS 7 rolled out, likely because the retailer has not updated its iPhone app to support the new operating system.

The proportion of negative daily app reviews for Target is higher since iOS 7 has rolled out.

Appnique?s data finds that Macy?s app has traditionally generated a low number of daily reviews and the reviews skew towards negative ratings. Since Macy?s is not generating a significant number of app reviews, there is not enough data to conclude how iOS 7 has impacted the retailer.

Walmart?s app also does not generate a significant amount of daily app reviews. Initially Walmart?s app dropped in average app reviews with the launch of iOS 7, but then leveled out to average roughly three daily reviews from the beginning of this week through Wednesday.

The sentiment of app reviews has not changed for Walmart as a result of iOS 7.

IOS 7's design is reportedly making consumers feel motion sick from the emphasis on zooming in and out and the fake 3-D effects, which might also be causing the increase in negative reviews for retailers.

Effect on Android
Although there are still more consumers using iOS devices than Android phones, there is a change happening as manufacturers such as Samsung are increasingly winning over consumers with bigger devices that have a more intuitive user experience.

Apple?s hold on high-end mobile devices is beginning to slow down as more low-price and similar devices hit the market.

With slumping sales, iOS 7 is clearly a bid from Apple to get some of its mojo back by taking cues from other manufacturers, which could give marketers a bigger incentive to more heavily target iPhone users versus Android consumers this holiday season.

This holiday season is also different from last year for marketers because of the uptick in cross-platform mobile consumers who own several devices from different manufacturers.

?It?s cool that Apple moved away from skeumorphic design, where the original text looks like raised buttons,? said Cameron Peebles, vice president of marketing at Airpush, Los Angeles.

?It?s making you feel like you?re using something you?re used to using, but now people are used to smartphones ? that was a huge thing,? he said.

Holiday impact
Given the initial impact on iOS 7 for marketers, the new software will make a big splash with marketers this holiday season.

IOS 7 makes it easier for marketers to develop universal iOS apps that are geared towards some of the more native features of the iPad.

As more mobile design moves towards gesture-based tactics, retailers can expect to see more engagement with apps this holiday season.

?IOS 7 makes it easier for developers to create mobile apps,? said Doug Dwyre, CEO of Mocapay, Denver.

?For retailers, it makes sense, too,? he said. ?Having the experience similar on the iPhone with that on the tablet is good.?

Take Victoria?s Secret, for example.

The retailer continuously uses in-app games and activities that are gesture-based and give consumers an incentive to re-open and use an app on a regular basis.

?If marketers can capitalize on swiping, it can get consumers more engaged,? said Scott Townsend, director of marketing at Urban Airship, Portland.

According to Michael Trapani, account executive at Xtify, New York, iOS 7 will be significantly big for retailers with a bricks-and-mortar presence.

?I think it?s going to be big for retailers because a lot are going to use location-based services and because you can swipe up to toggle that it?s so easy to turn them on,? he said. ?Any hyperlocal, even aisle-by-aisle [feaures]; the ease of use makes a big difference for retailers.?

Final Take
Lauren Johnson is associate reporter on Mobile Marketer, New York