Quick-service brands are increasingly developing mobile applications that offer more than just ordering capabilities in an effort to develop brand engagement and, ideally, drive traffic and sales in restaurants.

In general, mobile app development is a smart strategy for quick-service restaurants seeking engagement and conversions because that's where many of their customers are spending time, according to Chris Miller, executive vice president at foodservice market research firm Sandelman & Associates.

Forty-four percent of quick-service restaurant users have a smartphone, he noted, adding that 36 percent of people aged 16 to 34 who frequent quick-service restaurants spend 15 hours or more on their smartphone every week.

“The important thing to note is not only that heavy QSR users are more likely to own a smartphone, but they’re more likely to spend time on it,” Miller said. “It’s definitely a way chains can get engaged with their customers.”

Brian Blau, a research director at Gartner Inc., a technology research and advisory company, also noted that apps that involve features such as gaming and location-based services might help restaurant companies stay top-of-mind — an important factor in brand development. “A large part of the [apps] strategy is about engagement,” he said.

Here's a look at three such tactics that Burger King, Domino's Pizza, Krispy Kreme Doughnuts and McDonald’s are using to create effective and engaging mobile applications.