I personally wouldn't touch WhatsApp with a 10foot pole. As it is owned by Facebook, the company who earlier this year paid a company to compromise TAILS OS to find a pedo. Which its not the fact that they threw a pedo in jail. But the fact they compromised anonymity and in no way are a government body!!! So glowies be glowing hard at Facebook.
They also have done other spooky shit. Which is why the only reason I use Facebook is to sell my shit.
We could also talk about the OS and hardware your using to message people for security. If you want to know more read permanent record by Edward snowden. Its a great book and talks alot about PRISM and other spooky stuff