Telegram
Free
Telegram is a free cloud-based instant messaging platform.
Tox
Open Source
Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption.
LINE
Freemium
LINE is a new communication app which allows you to make free voice calls and send free messages whenever and wherever you are.
WeChat
Freemium
WeChat is a social media with instant messaging, commerce and payment services application.
WhatsApp Messenger
Free
WhatsApp Messenger is an instant messaging platform owned by Facebook.
Signal
Open Source
Signal is the most scalable encryption tool.
Franz
Free
Franz is a free messaging app /former emperor of Austria, that combines chat & messaging services into one application.
Zulip
Open Source
Zulip is a chat and collaborative software.
Compare GroupMe with alternatives
Compare WhatsApp Messenger and GroupMe and decide which is most suitable for you.