imessage
A free internet messaging service intended to be competing with WhatsApp. In stark contrast to aforementioned WhatsApp, which is like a box
made of glass where everyone can look into to see what you're talking about, iMessage is so secure that not even the FBI can sniff what you are talking about. Unfortunately, due to the fact that iMessage was made by Apple, it only runs on Apple devices. So while people with iPhones, iPods, iPads and Macs can enjoy securely talking on iMessage, WhatsApp still remains the leading application since it runs on Android and
Windows Phone as well. Heck, it even runs on
Symbian.