Method for enabling unwanted caller notifications or unwanted message sender notifications for all communication devices and applications including those with restricted programmatic call and message log access. The method delivers and stores a database of unwanted caller/message sender identification information in the device default contacts list, which is made available to the device's default caller/message sender identification service and to applications installed on the device. In one embodiment the unwanted caller/message sender identification information database is delivered as a separate synchronized address book, which can include additional unwanted caller notification information, for example the number or type of complaints about a given phone number.