1ty.me - If you need to send a password or some other form of simple but sensitive information to someone...

Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.

SafeNote - Encrypt and send files and notes with a link that automatically destruct after being read. SafeNote is a free web-based service that allows you to share a note or a file with confidentiality. There is no way to spying on you even to a hacker.

Conversations.im - XMPP client designed with ease of use and security in mind

Cryptgeon - Securely share self-destructing notes

Telegram X - Meet Telegram X for iOS and Android – two new official apps that offer more speed, longer batter life and smooth animations.