Truecaller's Caller ID & Number Locator is a mobile application that allows users to search and locate any caller's mobile number or fixed line phone number in the world. With coverage in 246 countries and 12,982 cities, this app provides the exact geolocation of the phone number, including the city area, state, country, and even service providers. The app also features a phone number locator that displays the city area, state, country, and service operator of the phone number on a map.

In addition to its phone number locator feature, Truecaller's Caller ID & Number Locator also offers a true caller ID and location feature that allows users to identify unknown incoming calls via the truecaller's caller ID with name and number location information. The app also includes a spam call blocker that enables users to block unwanted calls such as telemarketers, spam callers, and fraud. Users can easily manage their contacts with whitepages and blacklist.

Truecaller's Caller ID & Number Locator is powered by a database of thousands of areas information in the world, providing 12,982 cities areas codes for subscriber trunk dialing (STD) and 246 countries codes for international subscriber dialing (ISD). Users can easily search and lookup almost all the cities codes, with detailed phone number location info. The app also allows users to search offline, enabling them to look up the phone number, show true caller ID, and search STD code and ISD code without an internet connection.

Recent changes to the app include support for more countries and area phone number location. Overall, Truecaller's Caller ID & Number Locator is a useful tool for anyone looking to identify unknown callers and block unwanted calls.