CodyChat NULLED is the best all around chat software package we've come across that is available to the public.
It is very cheap considering how well made the software is and is only held back by its php backend which prevents it from being better able to support heavy usage and some specific features such as having more than 1 private message conversation at the same time.
The author fullstackdeveloper has offered the item for free, you can now download it.
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