What are some alternatives?
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Skype - Stay in touch with your family and friends for free on Skype. Download Skype today to chat and call on desktop and mobile.
MyChat - Secure instant messenger for any network
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
MagicPad - Free, simple, and private, offline text encryption suite.
WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.