Dave Winer is putting together a list of apps which can import, export, and/or edit OPML.

http://opml.org/compatibleApps.opml

That's a useful list. Not complete, though. I looked into OPML a while back to transfer outlines between programs. Here's what I found:

On Windows
- InfoQube imports OPML
- ConnectedText imports OPML
- Scrivener imports OPML
- Freeplane imports OPML using a script

On Android
- Mindly Pro exports OPML
- NoteLynX Pro exports OPML
- Orbit Mind exports OPML
- Halna Outliner exports OPML
- Alfred Fritz Outliner Pro imports and exports OPML
- Transno imports OPML
- MiMind Pro exports OPML

Undoubtedly there are more.

From long experience, and hours of grumbling frustration, trust but verify is the key with importing OPML produced from another app. The data transfer does not always work with 100% reliability due to syntax variations between apps.

satis wrote:

Dave Winer is putting together a list of apps which can import, export,
and/or edit OPML.

http://opml.org/compatibleApps.opml

I've been migrating my data from Dynalist to Legend by copying the OPML from Dynalist and pasting it into Legend. So far it has worked flawlessly. (Knocking on wood.)

Steve

For multiple platforms, NoteCase Pro also imports OPML.

Jon

The problem is that it seems that OPML only deals with plain text, not with the rtf formatting that various outliners boast of. So the formatting gets lost. At this point, I'm even having a problem with paragraphing (hard returns) being lost, but maybe that's just my lack of experience with OPML or I'm testing the wrong outliner. Looking at an exported OPML file from one of the outliners that boasts of its OPML export abilities, it certainly looks like plain text only--so the problem wasn't with the outliner that was importing the OPML file. If this is true of OPML in general, then it's a bit of a stretch to say that one can go from one outliner to another with OPML -- it's more like looking through a glass darkly....