The BBC's online podcast directory viewed on a mobile phone through the Nokia Podcasting application
What is an online OPML podcast directory, and why would I want to make one?
When used on mobile phones, online OPML podcast directories let people easily browse and subscribe to a range of podcasts without using a computer.
Nokia's Podcasting application includes compatibility with OPML directories. It includes several built-in online directories, and lets users add new online directories if they wish. The Podcasting app is included as standard on all of Nokia's current smartphones, which sell approximately 60 million units a year.
Online podcast directories are useful for anyone wanting to promote their own or other people's podcast feeds, because it allows users to browse and subscribe to that directory's podcasts directly on their phones.
Because online OPML directories are hosted on the directory owner's server or webspace, the owner of the directory can keep it up to date. This makes such online directories attractive to users, as the user can immediately see when new podcasts are added to the directory, and subscribe to them with a single click.
How do I use online OPML podcast directories on my Nokia phone?
See Step 6 below for end user instructions.
How do I make an online OPML podcast directory?
Online OPML directories are very easy to create, they can be made using a standard RSS feed reader. The following article uses Google Reader as an example, but other readers can be used instead.
Step 1: Using an RSS feed reader, subscribe to the podcast feeds you want to include in your directory
Open your favourite RSS feed reader, and subscribe to the RSS feeds of the podcasts you want to include in the directory. You may want to log into the reader with a new username to make sure your own personal podcast choices don't end up in the directory.
MP3, MP4 and most other audio formats should work in the Nokia Podcasting app. M4A files should also work and display images associated with podcasts, though they may not show chapter marks in Podcasting.
Step 2: If you have a lot of podcast feeds in your directory, arrange them into folders
Directories with long lists of podcasts are very difficult to navigate, so it's a good idea to put them into themed folders so that people can find the kind of thing they're looking for.
This can be done in Google Reader by selecting "Manage Subscriptions", and then the folder options next to each podcast:
Step 3: Export your subscriptions as an OPML file
When you've finished adding podcast feeds and arranged them into directories, you need to export your subscriptions as an OPML file. This can be done very easily in most feed readers.
In Google Reader it can be done by going to "Manage Subscriptions" and then clicking on the Import/Export tab. Save this file onto your computer.
Step 4: If necessary, rename the OPML file using the extension .opml
Note that many feed readers, including Google Reader, will export your OPML file with the extension .xml. This will not work as a directory in the Nokia Podcasting application, because it requires directory addresses to end in .opml
To solve this problem, all you have to do is just rename the OPML file with the .opml extension. For example a file called "podcasts.xml" should be renamed "podcasts.opml".
Microsoft Windows users please note: Some versions of Windows don't let you rename file extensions by default. To switch on the extension rename ability, go to the Windows Control Panel, select Folder Options, then the View tab, then untick the box that says "hide extensions for known file types", then click on "OK".
Step 5: Upload the OPML file to the web
You'll need a website to host your OPML directory file, so that users can access it through a single URL, and also so that you can update the directory whenever you want to.
If you're using someone else's site to host the directory, ask them to upload the OPML file in ASCII or application mode, then ask them what the URL is for the file after it's been uploaded. This URL is the address of your podcast directory.
Important Tip: Because people have to enter this URL on a phone's keypad in order to add the directory, it's important to make the URL as simple as possible. The simplest addresses are entirely in lower case letters, and they're as short as possible.
Note that address redirects will work with Nokia Podcasting, for example the CBC's official podcasting directory is at http://www.cbc.ca/podcasting.opml but this actually redirects to a slightly longer URL. However, the CBC advertises the shorter URL because it's easier for people to enter on their phones.
Once you decide on a directory URL, stick to it. Any changes in the URL will stop the directory working on the phones of people who have already entered the original address. If you absolutely have to move the directory to a new address, set up a redirect from the old address so that existing users aren't affected by the move.
Step 6: Let people know the directory's URL, and tell them how to add it to their Podcasting application
After you've created your podcast directory and uploaded it to the internet successfully, you can let people know about the address so they can add it to their podcasting application.
You might also want to give instructions on how to add directories to Nokia's Podcasting application:
1. Open the Podcasting application (it's usually in the Music or Applications folder)
2. Select "Directories"
3. Select "Options", then "New", then "Web Directory"
4. Give the directory a memorable name, then enter the URL (the address) of the directory, then select "Done".
5. Click on the directory name to update it, and when its icon turns yellow you can click on it to browse its contents.
Note that although OPML directories work on Nokia Podcasting, the standard isn't in any way connected to Nokia. OPML directories will work on many different podcasting applications running on many different kinds of hardware.
Step 7: If you want to update the directory, make a new directory OPML file and upload it on top of the old one
The whole point of online OPML directories is that you can update them to add new podcasts or update links.
To update a directory simply use the process above to export the new OPML file, then upload it to exactly the same URL as the old OPML file. Make sure that you've given the new file exactly the same name as the old file, so that it can replace it without changing the address.
The next time users access your directory they will see the latest version.
What about using OPML files offline?
OPML files created with feed readers can of course also be used offline, by transferring them directly onto a phone.
However, offline OPML directories have two major disadvantages over online OPML directories:
- Offline OPML files need to be manually transferred to the phone by the user
- Offline OPML files cannot be updated by their creator because they are not hosted online
But surely podcasts would cost too much to download direct onto a phone?
Most modern smartphones have Wi-Fi connections which can be used on home networks or public hotspots, and so completely avoid any phone network data charges.
Also, many network operators now offer cheap or flat-rate data connections which make it very plausible to download podcasts through the phone network too.