I've been using 1Pass OS X for ages (with Dropbox)
I just got an iPhone and installed 1PassPro straight up.
I'm a bit bummed out by the process of copy and pasting for logins with mobile safari but I'd imagine there are technical issues stopping a tighter integration.
The phone's memory holds the last password that you just copied when logging in.
Is there a quick way to clear the memory after you have pasted a password into a site via mobile safari?