Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Meetup for iOS and Android - Discover groups that are all about the things you love
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.
Conode - A simple editor to organize meetings
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Gathered - Make and share connections at events and meetups