Marketers are constantly debating about whether or not QR codes are beneficial to their marketing efforts. Ultimately, Coca-Cola, Toys R Us and Walmart have proven that mobile bar codes are not only beneficial, but also crucial in driving consumer engagement.

Over the past few years there has been a love/hate relationship with QR codes. Nowadays, the campaigns have gotten more sophisticated and companies are constantly placing mobile bar codes on billboards, bus shelters and products.

Here are the top 10 QR code campaigns of the second quarter, in alphabetical order. The initiatives were judged on creative, form of engagement and execution. Results for the campaigns were not provided.

Boston Market
Boston Market tapped QR codes to drive new and existing customers to its locations.

To add an incentive to get consumers to scan the mobile bar codes, the restaurant chain offered prizes.

The campaign, which runs through July 29, offers in-store consumers the chance to win a dream vacation to Maui for four, among other prizes such as sporting goods and gift cards when they scan the mobile bar code found inside every restaurant.

When consumers scan the QR code, they are encouraged to enter the grand prize trip.

Using mobile bar codes helps Boston Market make the campaign more interactive, as well as lets the company connect with consumers on a deeper level.

Additionally, consumers are more inclined to scan QR codes when there are prizes attached.

Brisk
Pepsi and Unilever?s Brisk Iced Tea let fans unlock exclusive content for the new Kinect Star Wars game via scannable Microsoft Tags printed on limited-edition bottles.

When users scanned the Microsoft Tag they were redirected to the company?s Facebook page and also had the opportunity to unlock exclusive Kinect Star Wars game content.

The campaign was a great way for Brisk to reach Star Wars fans.

Using mobile bar codes to let consumers unlock exclusive content is a great way to offer them something different.

Cadillac
Cadillac placed mobile bar codes on its print campaign that promoted the carmaker?s XTS model and featured calls-to-action that gave users different experiences based on publication titles.

The ad campaigns directed users to a campaign-specific mobile site that incorporated video, location and photos. The ads ran in several publications, including Fortune.

Specifically for the Fortune ad campaign, there were main pictures that highlighted specific features of the vehicle. Each photograph was framed by an image of a smartphone. The graphics were aimed at showing users that they could learn more about the car via their devices.

When users scanned the mobile bar code they were redirected to a mobile landing page where they could view videos or browse a photo gallery of the XTS model.

By placing QR codes on its static print ads, Cadillac was able to bring the campaign to life.

Coca-Cola
Coca-Cola is no stranger to QR codes. The company is constantly looking to make its campaigns better then the last and many times that involves mobile bar codes.

This particular initiative took place in Spain.

Users were able to see calls-to-action placed on the packaging that invited consumers to scan to view content such as UEFA?s Euro 2012 videos and Coca-Cola SmileWorld ? the brand?s online community.

Coca-Cola was smart to use mobile bar codes for the initiative, and even smarter to promote the campaign in a variety of ways, including a television commercial that illustrates how the initiative works.

Courtyard by Marriott
Earlier this year, Courtyard by Marriott rolled out QR code-enabled virtual concierge displays at 500 locations to make it easy for guests to access information about local attractions.

The new lobbies were decked out with 55-inch LCD touch screens showcasing information about local restaurants and other attractions that can be saved to a guest?s phone by scanning a QR code.

Guest can hold their device up to the QR code and automatically download information.

By incorporating QR codes within the hotel, Courtyard Marriott is able to provide its guests with a better experience.

Jamba Juice
While many companies use QR codes to drive user engagement, others such as Jamba Juice use the technology to build their database.

To build its email database, Jamba Juice placed QR codes on its in-store signage. In addition to growing its database, consumers can also opt-in to receive exclusive offers and discounts by becoming an insider.

When consumers scan the mobile bar code, they are redirected to the company?s mobile-optimized page where they can become an insider.

Using QR codes is a smart move for Jamba Juice as it encourages consumers to enter their information such as name, email, birthday, ZIP code and mobile phone number.

This lets the company learn more about its customers and better target them going forward.

Kenneth Cole
For Father?s Day, Kenneth Cole took a different approach to increase sales.

The retailer placed QR codes on its print ads that let consumers shop the company?s watch collection.

When consumers scanned the mobile bar code, they were directed to a campaign-specific mobile site.

From there, users were able to browse the company?s full collection of watches and choose to shop them via three department stores? Web and mobile sites ? Nordstrom?s, Dillard?s and Macy?s.

The campaign was obviously time-sensitive, therefore, by placing QR codes on its print ads, Kenneth Cole was able to read a broader audience.

Mobile bar codes present a great opportunity for marketers and are a great way to drive sales.

LA Galaxy
Soccer team LA Galaxy partnered with Shasta and SpyderLynk on a mobile bar code campaign that offered fans exclusive video content and rewards.

The mobile bar codes were featured on Shasta?s 12-Packs of Cola, Tiki Punch, Orange, Twist, and Grapefruit Zazz along with retail point-of-purchase signage.

When fans scanned the mobile bar codes they were able to access exclusive Shasta FlavorStyle videos which featured tricks and tips from the Galaxy Futboleros soccer entertainers.

LA Galaxy also incorporated social into its marketing efforts to continue a dialogue with consumers, even after they scanned the mobile bar code.

Social and mobile constantly go hand-in-hand and marketers are increasingly using both mediums to interact with users.

Toys R Us
Toys R Us continued its QR code push to promote more than 20 of its large outdoor items and let consumers visualize how the product would work and look in their own backyards.

Consumers could scan the mobile bar code next to the product with their mobile device to view video footage or images of the item fully set up.

Last year, Toys R Us rolled out a virtual store that let consumers scan QR codes featured on billboards and shop the company?s 2011 Hot Toy List.

On-the-go commuters and travelers in the New York metro area were encouraged to take part in the initiative.

Walmart
Walmart partnered with Procter & Gamble on a QR code campaign.

As part of the initiative, mobile bar codes were placed on bus shelters and trucks. Consumers were encouraged to scan and instantly buy products from brands such as Tide, Pampers and Gillette.

There were 12 bus shelters along the Magnificent Mile and Michigan Avenue in Chicago that were wrapped in a pop-up store experience.

The mobile storefronts featured nine limited-edition Olympic SKUs, as well as mobile bar codes next to products such as Bounty towels, Iams dog food and Pampers Cruisers.

When consumers scanned the QR codes, they were redirected to Walmart?s mobile site where they can buy the product.

Additionally, there was a P&G truck touring New York that gave out limited-edition samples to consumers passing by. Passerby were also given takeout menus that featured QR codes that let them shop the products no matter where they are.

The campaign was a smart way to drive user engagement and get them amped up about the campaign.

Final Take
Rimma Kats is associate editor on Mobile Marketer, New York