Hello is an official app from Facebook that let's you see all of the information about the telephone numbers that call you. Also, you can block specific numbers or not allow calls from private phone numbers.
Thanks to Hello, you can see who's calling you even if you don't have the number saved on your phone. The reason: if the phone number is listed within the Facebook database (which is very probable), the app will show you all of the relevant information when you receive a phone call.
If some of the contacts in your phone don't have a phone number listed for any reason, Hello will give you the option to sync the data manually. This process is simple, fast, and convenient.
Hello is a good addition to the phone app that comes installed on your phone by default, thanks to the fact that you can always (or almost always) know exactly who's calling you.
