NEW YORK -- Marketers and content owners need to understand that building custom applications is very different from partnering with existing applications, and mobile and PC platforms are different, though complementary.

According the keynote panel at digiday: Mobile applications are increasingly a vital component of brand marketers' overall strategy, creating a rush to develop and deliver content and advertising to consumers via on their mobile devices.

"Ask yourself before you do create an app, 'why do you want an app, what's the purpose?'" said Michael Burke, president of Appssavvy, a direct ad sales team for social media applications. "Look at existing apps and leverage activities people are taking part in.

"Think how does that play with your grand marketing strategy and your full social media strategy," he said. "It's all about figuring out what users are doing in the social space and on their handsets and how your brand fits in."

Applications that Mr. Burke believes got it right include "Four Square," "Where I've Been" and "Dogbook."

"What blows me away is the crazy amount of activity that takes place within this these apps," Mr. Burke said. "While it is still evolving, there are metrics out there -- you just have to look at what people are doing on the platform and the activity you want to encourage."

An important question that brands must ask themselves is whether they want to advertise within an application, run a site-takeover-type branding campaign, actually create and promote their own application or some combination of those options.

"Do you want to run ads within an app, become the exclusive sponsor of an app or do you want to own this?" Mr. Burke said "It depends on your needs and your brand's potential for longevity.

"Does it make sense to make an app for a single campaign?" he said. "Probably not, because you'll probably drive traffic for three weeks or so, but if you have the content and the team in place to invest in it long-term, yeah, go for it."

To promote an application, it helps to tie it in to an overarching campaign.

"How are you going to promote it?" Mr. Burke said. "Instead of asking consumers to text a keyword to a short code as a call-to-action in an ad, why not say ?Download this application to receive updates?'"

RockYou is an application developer and ad network that specializes in tying an application into a brand's overall marketing strategy.

"Build an asset for your company, not just a new cool thing," said Chris Wilhelmi, director of marketing at RockYou. "Will it move the needle, will it last, or will it be just a flash in the pan?

"If you're going to spend a lot of time to build something and you think ?If I build it they will come,' you're probably not going to be successful," he said. "You have to allocate the appropriate amount of money to promote the app to get where you want to get and have success.

"You need to market and promote your app to increase its discoverability."

RockYou has found that the lifecycle in terms of how long users engage with a given application is between 60 and 90 days.

If brands want to stick around on consumers' handset longer, they must continually reengage with consumers via ads, push notifications, viral videos, social media communities and other tactics.

"Extend the value proposition of your products and services with an app," said Matt Godard, CEO of R2integrated. "Brands are turning into publishers to take advantage of opportunities to distribute content via applications and integrating that into their marketing strategies.

Examples of applications that extend brands' value proposition that Mr. Godard gave include mobile banking and Lonely Planet's interactive mapping features for travelers.

"Think of it as an extension of the products and services you already have in an app environment -- that's the low-hanging fruit that will help extend your brand," Mr. Godard said. "When planning an app, look through lens of customers -- will they be passive or active users?

"Develop a tool for daily life to create an app that will be used on a daily basis," he said. "It's all about the strength of the value proposition you provide for consumers.

"Think of an app as a content type that can be distributed through multiple channels, and give it the marketing support it needs or it won't be successful."

Aside from proprietary and sought-after content with a built-in fan base of consumers, allowing publishers to charge a subscription rate, most applications that are successful either solve problems by having a practical use case or provide entertainment.

Aside from subscription, pay-per-download and ad-support, micropayments for virtual goods are a monetization strategy that is already exploding, especially on social networks and within social gaming applications such as Zynga.

"The virtual gifting world has become huge on Facebook, and it has become a major source of revenue within the ecosystem," Rahim Fazal, cofounder/CEO of Involver. "Advertisers are interested in branding and awareness campaigns within apps."

Free branded virtual goods can be used as a branding and loyalty tool.

For example, Rokio inserted virtual Sunkist cans inside one of its games applications letting consumers give friends a sponsored Sunkist can. The campaign drove millions of different interactions and ultimately raised awareness of the brand.

"You have to look at social networks as an audience development customer relationship management program -- look at Facebook and applications as a way of developing a relationship with your target audience," Mr. Fazal said. "It's also a source of retention and an opportunity to extend your brand.

"To promote your app, leverage the distribution channels you already have such as email and your Web site," he said. "Access an enthusiast group that is already partial to the brand."

Many savvy marketers are integrating applications for online social networks and smartphones such as the iPhone into their overall strategy.

"Try not to divide between the iPhone and Facebook when planning an app, because they're connected," said Jon Vlassopulos, CEO of Bellrock Media's Moderati. "In fact, there are more iPhone apps than Facebook apps, and the mobile application experience is better than the [PC] Internet, because you can take the content with you in your pocket."

To decide what is the best fit, each brand must ask itself, "What am I trying to do?"

"Very early in the application's life cycle, try to tell a story and connect with existing brand campaigns," Mr. Vlassopulos said. "Make sure the user experience on all platforms is connected and makes sense.

"Only create your own application if you're going to do it properly," he said.