Behind the Mic: 4 Things to Know About iTunes, RSS and Other Podcatchers

If you consume podcasts, you've probably discovered the joy of podcatchers -- applications which automatically keep track of the latest podcasts, download them, and transfer them painlessly to your favorite portable devices. Used correctly, they'll make your life MUCH easier and dramatically increase your podcast enjoyment. But to take full advantage of podcatchers -- especially the uber-popular iTunes -- you need to know a little bit about how they work. Read on for four tips every podcast lover should see.

1. A podcast doesn't have to be listed in iTunes for iTunes to automatically download it for you.

This is probably the most common issue we see among GWCers who use iTunes. Here's the deal: Unlike other podcatchers that scan podcast-enhanced RSS feeds directly by default, iTunes introduces another element into the fray. In order to provide you the awesome iTunes store experience, iTunes "accepts" podcasts from podcasters, scanning each podcast's RSS feed and adding pointers to each podcast episode to the store. When you "subscribe" to a podcast via the store, your copy of iTunes receives these pointers from the store, then retrieves the episodes.

Of course, you never quite know when iTunes will choose to scan a given 'cast's RSS feed, so there's often a delay between the time a new podcast posts via the host's site and the time it appears in the iTunes store. But here's the secret: While iTunes operates this way by default, your copy is quite capable of scanning RSS feeds directly on its own.

If you drop the Advanced menu item in iTunes and select Subscribe to Podcast (as described on our subscribe to podcast page) you can enter the RSS feed URL for any podcast -- whether it's listed in the iTunes store or not -- and iTunes will add it to your subscription list and retrieve the podcast directly without the iTunes store acting as the middleman. 

2. Due to RSS length limitations, you'll rarely see all episodes of a long-running podcast in your podcatcher.

As I mentioned above, podcatcher software looks for new podcasts by parsing RSS feeds. For archaic reasons, RSS feeds -- essentially big XML documents containing post titles, post text, and other additional fields (like links to podcast audio files) -- are limited to 512 Kb in length. Podcasts like GWC with over 250 episodes and long descriptions exceed this limit, causing come readers to truncate the feed, often with unpredictable results. Therefore such podcasts limit the total number of episodes in the RSS feed at any given time to assure the feed remains under the limit. In GWC's case, this is 50 episodes.

This does not, however, mean that previous episodes are not available. All GWC episodes are available for direct download. To download episodes older then 50 back from current, just locate the podcast on the GWC podcast page (or via this site's search function) and download it from the download link. You can then drag and drop this file into iTunes (or other podcatchers) to distribute it to your mobile devices just like you do the auto-downloaded files.

3. iTunes takes a while to accept podcasts.

Whenever podcasters submit a new podcast to iTunes, Apple follows an unknown process to "verify" that the podcast meets their standards before they "approve" it, causing iTunes to then periodically parse the new podcast's RSS feed and add its new episodes to the iTunes store. Though Apple seems to have streamlined this process significantly, it can take from a few days to a few weeks for new podcasts to appear in the store.

During this period there is nothing a podcaster can do to accelerate or change the process. Each 'caster submits his or her podcast -- and waits. This is why you almost never see a podcast on iTunes the day after its creator announces its availability. Remember #1 above, though. You don't have to wait for iTunes to approve a podcast to listen to it through iTunes, or even to tell iTunes to automatically download it for you.

4. Even after iTunes accepts a podcast, it won't show up in iTunes store searches immediately.

Because of the huge amount of data that Apple must index to allow you to search for podcasts, Apple updates their search indexes in rounds. This means that any new data added to the store might not enter the search indexes for a period of anywhere from a few days to a few week. (It's usually closer to a few days, but you never know.) If you're trying to find a brand-new podcast on the iTunes store, you're better off seeking out the link from the podcast's owner and linking directly to the 'cast's iTunes store page. Once you subscribe, this limitation no longer matters you you. You'll automatically receive new podcasts as they become available (and iTunes scans for them, see #1 again).

To sum up: If you're in a hurry to grab a newly-released podcast -- like if, for example, you're heading out the door for a trip and want to grab the most recent GWC 'cast -- you can always download the 'cast from any of our direct download links, then drag and drop it into iTunes for distribution. And if you're waiting for one of our newly-born additional podcasts to show up in iTunes, you have other options available for listening to it right away.