Not all 4G networks are created equal. The iPhone 5 officially hit T-Mobile on Friday, April 12, but not all T-Mobile iPhones are created equal. You can buy a phone from T-Mobile itself, or an unlocked one from Apple that comes with a T-Mobile SIM, but not every iPhone for sale is compatible with T-Mobile’s 4G network. Many customers are going home with an older version that’s not compatible with T-Mobile’s network, defeating the point of owning a 4G LTE device. The problem is that many T-Mobile and Apple Store employees aren’t aware of the difference.

What customers need to look for are phones that say 1700/2100 right on the box: these unlocked phones are compatible with the T-Mobile 4G network available in most cities.

Arthur noticed this when his shiny new phone, which he paid nearly $700 for up front including sales tax, had slower data speeds than his previous Android smartphone. That couldn’t be: but it was. That’s because T-Mobile hasn’t rolled out their LTE network, on the same frequency as competitor AT&T.

Arthur writes:

I called T-Mobile, twice, and asked them if there would be any differences between the unlocked iPhone in the Apple Store and the one they would get, and both times was told the only advantage was being able to pay off the phone over several months.

The phone worked pretty well, but I noticed I didn’t get 4G speeds nearly as frequently as I had with my Android. Just today, I found out why—the unlocked iPhone is not, in fact, identical to the T-Mobile model. T-Mobile has two versions of what it calls 4G—the HSPA+ network I’d been using on my Android, and the more recent (and much more limited) LTE network. The iPhone the T-Mobile reps had encouraged me to buy picked up only the latter, which is not available to nearly the extent of the former.

Today I called T-Mobile. The first rep understood the issue, but didn’t quite know what to do about it. He put me on hold and said someone more qualified would speak to me about it. After about five minutes, a T-Mobile tape informed me I could get a callback instead of waiting. I took them up on it, but the person who called back was not an expert, and had no idea what I was calling about.

Silly customer, expecting customer service representatives to know anything about their own company’s products. Over at Gotta Be Mobile, their dogged reporters figured out what’s happening just by… walking in to an Apple Store and asking about the T-Mobile phones. They found that Apple Store employees had no idea that they shouldn’t just be grabbing any old unlocked iPhone 5 and selling it to their customers who have T-Mobile.

When we went to two different Apple stores in [redacted], none of the salespeople we talked to were aware of the issues and tried to sell us the old model, insisting it was completely compatible with T-Mobile’s networks. We had to show the Apple store employees this Apple support document that clearly states the limitations.

T-Mobile USA: Understanding network compatibility of an unlocked iPhone 5 [Apple]

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