App needed

[10i]

I wonder if there is an app that can scan my address book and tell me which mobile network each person is on.
Reason being I have Telkom mobile free minutes and sms I want to use without manually checking who is on what network.

 

[seanyp00h]

Because of number portability it isn't possible to know which number belongs to which network just by using the prefix - 082,083 etc