Note that Antox is still alpha software and there may be some bugs. Antox uses the Tox protocol which is Peer to Peer, so there will be high data usage and battery drain. WiFi only mode is currently recommended for now. Antox is completely open-source.
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Pros
Pro Free, open source
Antox is licensed under Creative Commons with source code available on GitHub. Being open source makes it possible to make sure your messaging are not controlled by a corporation.
Pro Peer-to-peer
There is no middleman, all communication happens between the users.
Cons
Con High data usage
Antox uses the Tox protocol which is Peer to Peer, so there will be high data usage and battery drain. WiFi only mode is currently recommended for now.
Con Still in early development
Antox is still really early in development, being in beta currently.
Con Battery drain
Antox uses the Tox protocol which is Peer to Peer, so there will be high data usage and battery drain.