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

Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.

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.

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.

Cryptgeon - Securely share self-destructing notes

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