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It has no in built fax function (and nor has any mobile phone to my knowledge for many years now). There might be a third party app out there, but I assume it would be using their service as a gateway somehow and there's probably some form of subscription involved.
 
There are many online fax services, some are free, and some require a sub. There are also apps that will allow you to send and receive faxes, available in the app store. Google is your friend...try it!
 
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