Here's how I understand your situation. You listen to podcasts regularly on your phone, but would like to access them on your computer as well. Additionally, you'd like your phone and computer to synchronize played episodes, downloaded episodes, settings, etc. However, you'd like to be able to access old podcast episodes on your phone that might not have synchronized.
As I see it, here are your options.
If this is a rare occurrence and you have dropbox, this honestly might be simplest.
- Open iTunes
- Download the Podcast Episode
- Drag the file from iTunes library to Dropbox
- Open in Dropbox on iPhone
If this is happening often, you have a couple additional options.
Use this method if you don't often listen on your computer, and can live without played podcasts being synchronized with iTunes. This is what I do because I listen primarily through my phone. It's simple, and works great. In my opinion, the podcasts app for iOS works more efficiently as a standalone and gets wonky when you try to manage the synchronization with iTunes.
The Advantage of this method is you can see old episodes directly on your device. The tradeoff is you lose synching, which may or may not be important to you.
- Open iTunes
- Connect your iPhone
- Click on the iPhone icon to see your device
- Click on "Podcasts"
- Uncheck "Sync Podcasts"
Now on your iPhone
- Open Settings
- Open Podcasts Settings
- Change "Auto Downloads", "Episodes to Keep", "Cellular Data" settings to suit
- Open Podcasts App
- Check podcasts for old episodes.
- If old episodes aren't there, you may need to delete and re-subscribe through the podcasts store (top left button)
EDIT: See @jstaryu's answer above for simple drag & drop - it's actually much simpler than the manual method below. If you decide to go manual - you should probably accept his answer as "the answer". But I'll leave my version here for true manual hard-core podcast management.
You can manually add episodes to your iPhone. The advantage of this method is that you can keep synching the way you have been. The disadvantages are you have to have access to your computer, it gets tedious if you do this often, and you have to also manually sync your music / videos.
- Open iTunes
- Select "Podcasts" from the upper left pull-down
- Select the Podcast you want
- Right / Control-Click the Podcast Title (on the right)
- Select "Show All Available Episodes"
- Download the episode you want
- Put a check next to the episode
- Click your "iPhone" on the top right
- On the "Summary Page" scroll down to "Options" and make sure "Sync only checked songs and videos" is selected.
- Re-synchronize your iPhone with iTunes. The new checked podcast(s) should be there.
WARNING - this will impact music / video synching as well. You'll need to manually check-all or check the ones you desire to keep.
Hope this is helpful.