1) Login the POS with admin user and go to, tools-->security controller-->security manager-->click the edit button beside the user to whom you want to use WhatsNow.
2)If you want to use WhatsNow for the user Ravi then press edit button beside the user Ravi and enter the e-mail id,mobile number and save.
NOTE: The mobile number should be the one in which you are going to use WhatsNow.
3)After configuring the user in the security manager,please go to help-->About -->Add on license-->click on map user which is beside whats now.
4) Enable the user "Ravi" by double clicking the check box and close.After closing,press "Sync" button to sync the user.