I think they do exchange products purchased from their online store though but I suppose they're the same company.
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Did you tell them it was purchased at Best Buy? What was wrong with it?
They never asked. I wasn't being cagey either.
We were on vacation and the phone would not hold a signal. Kept giving "no SIM card" error. I figured I would get better service at a random Apple Store than a random BestBuy.
Went in, described the problem. He punched some numbers from my phone into his device (this is likely where he was confirming authenticity and eligibility). Then went into the back and brought out an all new iPhone.
As posted, I think Apple will cover any legitimately sold Apple product.