Callware is known for its Callegra.UC product,[1] which provides voicemail, unified messaging, auto attendant, text to speech (TTS), voice recognition, and clients to access voice and fax messages from the telephone, desktop client, or the Internet.

In 1994, Callware Technologies was incorporated[18] as a result of a spin-off from International Voice Exchange, a service bureau and software development company founded in 1988.

Subsequent versions integrated Callegra’s GUI with Novell GroupWise, Microsoft Outlook, Lotus Notes, and various web browsers.

[19][20][21] In 1998, Callware started providing Callegra to government agencies and the US Department of Defense (DoD).

Callegra.UC added a .NET Web Service, allowing custom client applications to be developed for the Callegra.UC unified messaging and communication product.