Adium is an Open source multi-protocol instant messaging client for Mac OS X, supports MSN, Jabber, Yahoo! and other networks.

Bleep is a fun and easy instant messaging app that is completely private.

Digsby provides you with IM, email and Social networks in one easy to use application.

Empathy is an instant messaging (IM) and voice over IP (VoIP) client which supports text, voice, video, file transfers, and inter-application communication ov…

Fring connects with Skype, MSN Messenger, ICQ and Google Talk from your iPhone.

Hangouts is an instant messaging software developed by Google.

AIM is a instat messenger application.

Conversations is an open source XMPP/Jabber client for the Android platform.

Disa is your new messaging hub. Conversations from different services can seamlessly be joined together, or disbanded within seconds.

Facebook Messenger is the official Facebook app that lets you have text conversations with all of your friends on the popular social network.

Gaption is a Social networking platform that enables people to monetize their content, products, and social networking activities.

IM+ supports simultaneously major IM services, including Google Talk, Twitter DMs, Yahoo!, AIM/iChat, ICQ, Jabber (and Slack through Jabber), etc.