To track messages in someone else's WhatsApp account, WhaTracker software exploits a vulnerability in the cellular operator's data protocol to intercept SMS message with a verification code required to transfer an account to a new device. Before tracking someone else's WhatsApp account, the client needs to specify the phone number of a target user whose message history s/he wants to track. The application will request from WhatsApp to restore access to the target account, and then intercept the SMS with the recovery code. Once the target account has been hacked, the user will be able to log in to their WhaTracker account and start using the WhatsApp message tracking application for their own purposes.