A growing number of millennial-friendly retailers are handing over their social media accounts to celebrities, who are providing a range of content in a bid to drive customer engagement and attract new fans.

Brands such as Victoria?s Secret and Express are tapping their spokesmodels and other social media-savvy mavens to leverage the celebrities? millions of followers and offer fun content in line with the retailer?s image. Many retailers would be well-poised to leverage this tactic, but must look at social media usage and mobile data for their target demographics to make an informed decision of which celebrity to team up with.

?Celebrities have influence and reach that can transform the way consumers think about brands and how they purchase products,? said Misha Talavera, chief marketing officer and co-founder of NeoReach, Palo Alto, CA. ?Partnering with celebrities is a powerful way for brands to expand their customer base and increase their brand equity.

?In particular, social media celebrities - who, according to a report by Variety, are more popular among millennials than traditional celebrities - have been proven to drive huge returns on investments,? he said.

?Although short-term strategies can be extremely powerful, in particular for a new product or movie launch, we at NeoReach have found that long-term partnerships between brands and influencers foster more authentic relationships and content, and the brand often pays a better price (eCPM).?

Innovating social media
Consumers are used to seeing retailers post behind-the-scenes looks of campaigns or curated weekly must-have items on their Instagram or Snapchat accounts. While those posts may strike some customers? fancy and prompt them to shop on mobile or in-store, they may also come across as stagnant, with little engagement value.

Consequently, brands are now turning to celebrities to shake things up on social media and offer followers a different perspective. For example, lingerie marketer Victoria?s Secret has been giving several of its new Angel ambassadors its Instagram and Snapchat accounts to document whirlwind press tours for the new Body by Victoria line.

Model Sara Sampaio was in charge of Thursday?s Instagram feed, and posted selfies and images of herself talking to press, signing autographs and getting ready in the makeup chair.

Meanwhile, millennial fan-favorite Express tapped actress Ashley Benson to take over its Instagram channel last week. Ms. Benson posted photos of herself wearing several of Express? new denim styles while running errands and working on her ABC Family television show, Pretty Little Liars.

Each brand's choice of celebrity made sense for its overall mission and had relevancy to their client base.

?The influencers you pick for your campaign will make the difference between a 10:1 ROI and a flop,? Mr. Talavera said. ?Each brand has their own target demographic, some are more niche than others.

?However, the beauty with social media is that practically every single buyer persona is using it,? he said. ?From sixty-year-olds to Gen-z, surfer bros to suits and ties.

?Now, they don't all use the same social media in the same way. Therefore, it is crucial for brands partnering with influencers to really dig down into the influencer's follower demographics and psychographics, to ensure they partner with influencers that speak directly to their target audience.?

The right choice
Brands that opt to use this strategy to gain more followers and stir up buzz on mobile must look at three variables for choosing the ideal celebrity to join forces with. They must examine the potential influencer?s reach of engaged followers, the content he or she regularly posts and audience age range.

Retailers with younger followings will likely see the most success with this type of marketing effort, although other brands should not rule it out.

?This strategy tends to works best for mid-tier lifestyle brands that are easily accessible and affordable for middle-class, everyday customers,? said Vanessa Horwell, chief strategy officer at ThinkInk, Miami. ?Categories such as beauty products, athletic wear and health supplements fare well, for example, because they are so embedded into consumers? daily routines.

?When consumers see their favorite celebrities actively using these products, they immediately associate the celebrity?s success and caché with the product and their own aspirations for success,? she said.

?By contrast, luxury items tend not to fare as well, especially at a time when upper-class, elite consumers are under public scrutiny because of society?s current focus on income disparity and wage/salary gaps. Non-elite consumers are unlikely to appreciate reminders or publicity about products they cannot afford or enjoy.?

Brands that already have famous spokespeople or models on their roster would be wise to encourage them to do a social media takeover, especially ahead of big sales, new product launches or holidays.

?The rising generation of consumers are digital and social mavens,? said Rob Gregory, chief revenue officer of WhoSay Inc., New York. ?They identify with their celebrities in a mobile environment.

?On the brand side, it works better for some brands than others based on the willingness of the brand to relinquish some control and endure a few cringeworthy moments. I think the equation that is different for every brand is, if there are a few moments of off-brand dissonance worth it for some powerful authenticity moments.?

Final Take
Alex Samuely is an editorial assistant on Mobile Marketer, New York