Truecaller app allows users to find out who is calling or messaging them. This is ideal when you don’t have the number saved in your contacts as you can know before picking up the call if you should answer or reject.

source https://gadgets.ndtv.com/how-to/features/truecaller-change-name-delete-account-business-how-to-android-ios-steps-guide-2446637#rss-gadgets-all