Shake Shack's  (SHAK) new mobile app accounts for less than 3% of its domestic sales but adoption is growing rapidly, CEO Randy Garutti said Wednesday.

The burger chain launched its Apple (AAPL) iOS app nationwide in January following a trial run in October. As of May 31, about 340,000 people had downloaded the app.

"It's been a short time and already we've had 3% of our sales through the app," Garutti said at the Piper Jaffray Consumer Conference on Wednesday, adding that most consumers don't even know an app exists allowing them to skip Shake Shack's notoriously long lines. An Android app is expected later this year.

"More than ever people are going to get whatever, whenever they want," he said, comparing mobile app ordering to Amazon's  (AMZN) drive-thru grocery stores in Seattle. "I don't believe my children will wait in line for anything in their lifetime."

Garutti cautioned that the in-store eaters is still crucial. "You still need to be the place where the Little League goes, or where you take a date, or a business meeting," he said, arguing that technology facilitates the experience. "There's no doubt that this is a huge part of our future."

Shake Shack is also experimenting with its menu. Garutti said the company is testing "Nashville-style hot chicken" at six locations across the country, including the Midtown East location in New York. The concept may expand, depending on consumer preferences, although Garutti noted that Shake Shack didn't add barbecue to its menu despite the limited-edition product's popularity.

Another food innovation available in New York can be found at the Madison Square Park original location, where Shake Shack began offering breakfast last month.

"We still have a ton to learn about people's preferences," Garutti added, reiterating Shake Shack's commitment to basic fast food. "We don't want to have foie gras on burgers."

Visit here for the latest business headlines.

More from Stocks

Dow Gets Swept Into Nasty Reversal Even as Nasdaq Posts New Record

Dow Gets Swept Into Nasty Reversal Even as Nasdaq Posts New Record

REPLAY: Jim Cramer on Fed Rate Hikes, Oil Prices and Starbucks Worries

REPLAY: Jim Cramer on Fed Rate Hikes, Oil Prices and Starbucks Worries

What Will GM Do With Cruise -- and Is Its Stock Worth $55?

What Will GM Do With Cruise -- and Is Its Stock Worth $55?

3 Must Reads on the Market From TheStreet's Top Columnists

3 Must Reads on the Market From TheStreet's Top Columnists

This Should Be Your Retirement Savings Plan When the Stock Market Crashes

This Should Be Your Retirement Savings Plan When the Stock Market Crashes