Fwiw, I put the sim from my Focus into my Inspire 4G, entered some APN settings someone posted on the at&t online forum, and its all good. To my knowledge, I not on a 4G plan for my Focus.
Not sure what it means, but the 4G indicator "H+" on the Inspire shows that it's available, and that I'm even connected at times. It will show "E" sometimes, also. I don't think there's a separate 3G indicator. At least I haven't noticed any, nor do I see one in the quickstart that came w/the phone.
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