Just how important is design for building a killer mobile experience? According to founders and top execs at sites like Etsy, GroupMe and Stamped, it's downright vital.

"We think it adds strategic value," says Bart Stein, the co-founder of recommendation app Stamped. The fact is, "it's hard to stand out based on product alone," he adds. "We treat design, engineering and marketing as three pillars of our company."

Stein, along with GroupMe's co-founder Steve Martocci and Leland Rechis, Etsy's director of mobile, recently pondered the process of creating and designing mobile experiences during a panel discussion entitled "Design and the Mobile Startup: NYC Edition." That chat was part of Internet Week New York, a festival of web-focused events that ran through last week.

At Stamped, for instance, the designers don't just make the site's graphics look pretty. They design the product, which is a platform where friends recommend destinations by stamping them with their approval. "The designers dictate a lot of what the product is becoming," says Stein.

Related: What Makes Facebook Worth So Much

Stamped's team looks at what people are doing offline for inspiration. "No one sits around like 'this place is mediocre, yeah this place is mediocre, too, let's go there,'" says Stein. "People like to tell their friends about the best thing."

The same goes for new mobile apps. To trigger conversation about your product and sharing too, you'll want to create an experience that people will want to recommend -- that is, you'll want to avoid being mediocre at all costs. So what does this mean for aspiring tech entrepreneurs and those just starting up?

Design must be a top priority from the start, up there with coding and building out your system. "It's really important to have a designer that is a part of the founding team," says Stein. "I don't think you should treat it as simply an afterthought and just hire only engineers and then hire a bunch of freelance designers later."

Related: Branding's Big Guns

Rechis echoed Stein: "We look at product design as the thing that bonds the design group and product management group." At Etsy, all the designers know how to code, and the product managers know how to code. But the designers get things done, he adds.

That added flush of design may also stand between you and the competition, notes Martocci whose company was acquired by Skype for $85 million last year. The look and feel of a product or set of features will be what separates most businesses from each other and it'll help a company build its brand. That kind of recognition is what consumers want, besides great functionality, of course. "It's hard to build a product," he says. "It's a constantly evolving process." Why not make it easier?

What advice would you add for startups looking to make a memorable mobile experience? Leave a comment and let us know.