Can anyone recommend one?
I would like to read my Palm .PDB and or mobi files.
I don’t think that’s possible with your phone.
Not my phone yet, they are going to buy us new ones for work. Perhaps I’ll ask to stay with the won’t-fit-in-my-pocket Blackberry. 
The Rugby and Rugby Pro are Android phones. For those I’d recommend FBReader.
Thanks, yoyodyne!
But the OP asked about the Rugby II which is very different - it’s a flip phone, not a touchscreen phone. There’s absolutely no mention of Android in the specs or description, so I think it’s a non-smartphone (aka “featurephone”). I don’t think you can install third-party apps (like e-reader apps) on it.
Hence post #2.