I connected to my local POP3 mail server with the default app, and it worked fine... for a little while. Then it started claiming it couldn't connect - and funny enough, it would never accept email from the New York Times. (Political special-casing?) So I installed K-9, and that seems to work much better. I keep a ton of mail on the server, and K-9 doesn't seem to have a problem with that. I am not associated with the developers of K-9, just a user. FYI.