apple
Find Out Who’s Calling You With Number Guru
As it stands the app covers 100% of US landlines and about half of US cellular (not to be mistaken with the carrier US Celluar) numbers. The app can also identify the carrier that the call came through about it seems that it is unable to identify those customers who have ported out of a certain carrier and ported in to a different carrier while retaining the same number.
The app also asks for you to share your contacts with them although it is not stated why, so probably something you might want to think twice about before doing so. All in all a rather nifty app to help identify who called, after all it gets quite annoying calling back unknown numbers only to find out that they dialled the wrong number to begin with and waste your time. Good way to avoid telemarketers too.