This still seems minor. If someone is able to get the number doesn't that spell larger issues than whatsapp? I get the point being made and I understand the potential issue, but I don't see how its a major security problem with whatsapp as I figure things are probably compromised anyway if the user is able to get the IMEI to begin with
even if you have the users phone nurmber and imei nuumber one would assume u already have access to other info then anyway so who cares about whatsapp
Can you easedrop on whatsapp sessions from another phone using this info?
