To completely remove Dapper:

  1. Quit Dapper
  2. Drag the Dapper app to the trash.
  3. Open a terminal (Applications->Utilities->Terminal) and type:
  4. defaults delete com.map-pin.Dapper
  5. rm -Rf ~/Library/Containers/com.map-pin.Dapper
  6. Empty the trash
  7. Reboot