How to save WhatsApp from Wi-Fi hacking?
WhatsApp doesn’t have a very secure server, so avoid using WhatsApp when on Wi-Fi.
Generally, Android and Apple devices that use WhatsApp do not have any security. It is Blackberry devices that are extremely safe as they use their own server, while others use the WhatsApp server.
So, generally, avoid using Wi-Fi for WhatsApp, if and whenever it is possible.
In a situation, where you do not have internet connection and Wi-Fi is the only option, use the Wi-Fi network and then ensure that you go to Settings-Chat-Settings-Clear All Conversations.
By doing this, you will lose out on all the messages, but this will help your data free from being accessible to anyone else. Always make this as a habit. All the media files will be saved on your phone, so you aren’t losing any of your media file data.


How to save WhatsApp from IMEI hacking?
Do not give your device to stranger who is curious to know how your new phone functions and how classy your smartphone looks.
Avoid sharing your phone number with such people and do not let them see your IMEI number on the phone. One can easily read the IMEI number without even opening the phone.
Dial *#06# and press the call key. Your IMEI number will flash on your screen.
Never share your IMEI number and avoid keeping your phone out at places where it can be accessible to others. Once the user has your IMEI number, he or she can easily hack your device and read all your messages.

Each and every device’s WhatsApp account is associated with IMEI number as the password so whenever anyone changes her/his device (changing from one phone to other, from phone to tab etc. for example from iPhone 5S to iPhone 6), WhatsApp sends the notification and asks to re-verify the account.