Hi Raza, as a marketer you must be using SMS marketing strategy. I would like to recommend you a tool which can be helpful to you for enhancing the SMS marketing strategy.
"Export Contacts For WhatsApp", an Android Application that helps a user to export the list of contacts which are using WhatsApp from the bulk of contacts (Up to lacs)!
It can help you to get the 'Right Audience'! Hope it will help you. :)
Like to download this app: https://play.google.com/store/apps/details?id=com.ebizzinfotech.whatsappCE