To uninstall PhoneView, simply drag the PhoneView icon to the Trash icon on your dock. To delete any archived data, trash the folder located at:
(your home directory)/Library/Application Support/PhoneView
Note that in OS X 10.7 and newer, the Library folder is hidden. To open it, choose "Go To Folder..." from the Finder's "Go" menu, and enter:
and then press the Go button.