I "lost" Nimbuzz that way. Since it's one I download from its own website, I downloaded the newest version and installed. Installation didn't work, and old app would no longer launch. So then I uninstalled old app and tried to reinstall from the previously downloaded version but now that version wouldn't install.

So now I have Meebo. And that's fine, it's just that Nimbuzz also had Skype, which was handy.