How does the business of podcasts look to the people running it? A new survey suggests that even as interest in podcasts increases, much of the growth of the business is coming from existing listeners rather than new listeners. And podcasters are concerned about finding new audiences and monetizing.

Clammr, the company behind an iOS app that helps users share and discover streaming audio content, conducted the online survey of 59 podcasters. Most of the respondents were “independent podcasters of the type who represent the vast majority of podcasts that are being produced,” Clammr co-founder Parviz Parvizi told me, “not large brand-name shows with NPR or big-media company links.”

These aren’t the Serials of the world, but the little guys running their podcasts without the help of larger organizations.

Among the survey’s findings:

— Interest in podcasts has increased: There was a 32 percent increase in the volume of Google searches for “podcast” between 2014 and 2015, and a 37 percent increase in downloads. But Clammr suggests that “underlying growth is being driven more by increased listening from existing users than by growth in the underlying user base,” and found that “May 2015 Google searches of podcasts are lower than the January 2006 peak of the previous podcast moment.”

— Here are the aspects of podcast development that the survey’s respondents are satisfied and dissatisfied with:

In other words, it appears podcasters are generally happy with the tools at their disposal but are concerned about the tougher task of growing their business.

— Despite that dissatisfaction with social media, social media is still the main way that podcasters drive growth:

— Apple has facilitated the growth of the podcast business. Eighty-two percent of smartphone podcast listening is on an iOS device, while only 16 percent is on an Android device. And 78 percent of those who listen to podcasts on an iPhone do so through Apple’s Podcasts app.

The full results of the survey are here.