The APN settings for Straight Talk are as follows. Set the APN to "tfdata" and the proxy to "proxy.mvno.tracfone.com." Set the MMSC to "http://mms-tf.net" and the MMS proxy to "mms3.tracfone.com." The MMS port should be set to "80" and the APN type is "default.supl.mms."
Set the MCC to "310" and the MCN to "410." The name of the APN is used for your own personal reference only and can be set to anything you wish. The username, password, server and port should be left blank and there is no need to set an authentication type either. Android users should leave the APN protocol on the default setting.