Tox
Open Source
Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption.
Imo
Free
Imo free video calls and chat is a kind of Communication apps for Android.
IM+
Freemium
IM+ supports simultaneously major IM services, including Google Talk, Twitter DMs, Yahoo!, AIM/iChat, ICQ, Jabber (and Slack through Jabber), etc.
iMessage
Free
iMessage is an instant messaging service.
Tencent QQ
Free
Tencent QQ (QQ) is an instant messaging software service.
Trillian
Freemium
Trillian is a proprietary multiprotocol instant messaging application.
Facebook Messenger
Free
Facebook Messenger is the official Facebook app that lets you have text conversations with all of your friends on the popular social network.
ICQ
Free
ICQ is an open source instant messaging software.
KakaoTalk
Freemium
KakaoTalk (Korean: 카카오톡), or sometimes KaTalk, is a free mobile instant messaging application for smartphones with free text and free call features.
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