Podcasts may be having a moment, but it is happening almost exclusively on Apple devices. According to research published this month by Clammr, 82 percent of all podcast consumption happens on iOS, Apple’s mobile operating system, compared to just 16 percent on Android, the mobile operating system developed by Google. This disparity becomes even more striking when you consider the fact that Android leads Apple in the global smartphone market, 53 percent to 46 percent.

Despite having a larger share of the global smartphone market, Android lags far behind Apple in its ability to drive podcast listens. Clammr / Slideshare

The iOS operating system offers a level of support to podcasts that’s absent from Android. Apple made Podcasts, its own podcast app, a native, preinstalled part of iOS last year, and its marketplace for media, the iTunes Store, foregrounds podcasts in a way that its Android counterpart, Google Play, does not.

Thanks to breakout shows like “Serial” and “Invisibilia,” increased investment from public and private media companies and the growth of recap podcasts, podcasting has been ascendant in recent years. More than 42 million Americans have listened to at least one podcast in the past month, and we now listen to 21 million hours of podcasts every day, according to Edison Research. According to Apple, it has more than 285,000 podcasts in its iTunes Store.

Yet despite that enthusiasm, it remains to be seen whether podcasting can become a mainstream media format. While global Google searches for podcasts are up 32 percent compared to the same time last year, and podcast downloads are up 37 percent, most of the downloads are being done by pre-existing fans, rather than new ones: There has been a 53 percent slowdown in the rate of monthly penetration growth, according to Clammr’s report.

Podcasters also face an uphill battle convincing advertisers that the medium is ready for primetime. The Interactive Advertising Bureau, which regulates digital advertising formats, has not yet formally settled on a definition of what a podcast is, making it difficult for advertisers to buy at scale.