Very easy to use
I have been using eFax for over 10 years and they keep improving the way you receiving and sending fax. The iPhone app is one more way to easily send out fax by taking a picture of the document you like to send. If you know how to operate a camera, you know how to use it. App is great and is free for eFax subscriber.
Slampand about
eFax App–Send Fax from iPhone