iMessage alternatives

iMessage
iMessage lets you send messages back and forth with anyone on iPad, iPhone, iPod touch, or a Mac. If you’re a texter, you’ll love Messages on iPhone, iPad, and iPod touch. Now they all come with iMessage, a service that’s an even better kind of texting. Because it’s free for you and anyone texting over Wi-Fi using an iOS device or Mac with iMessage.
iMessage alternatives are:
WhatsApp, Google Hangouts, BBM, Facebook Messenger, iChat
Here are the latest news about iMessage:

2015 iMessage and FaceTime get two-factor authentication


Apple has improved the security of FaceTime and iMessage, its voice/video and multimedia chat communication tools. The services received two-factor authentication as an option for users to enable, meaning that even if someone uses their Apple ID email and password to enable iMessage or FaceTime on a new device, they’ll still need to use a PIN from an existing trusted device to gain access to those services. If you’ve previously enabled two-factor for iCloud, it’ll also be enabled to FaceTime and iMessage. The additional level of protection applied to these services helps ensure that people will have a harder time grabbing potentially private images from your iMessage history, or pretending to be you via online communication methods.