The HTC EVO is a sophisticated and pretty sweet smartphone that runs on Android and is exclusive to Sprint. That’s all pretty normal. What isn’t normal is that Sprint is charging EVO owners a $10 fee above the cost of their normal data plan–an unlimited data plan–and no one at Sprint can really explain why. Promotional materials claim that the fee is for a “richer data experience with an advanced processor,” which makes no sense. They might as well call it an “awesome phone fee.”

There’s now an entire site devoted to the subject, logically named explainthefee.com. The site’s author received this response from a Sprint PR representative

The $10 per month Premium Data add-on gives the user a richer data experience on HTC EVO 4G than ever before at both 3G and 4G speeds, taking advantage of features including an 8MP auto-focus camera with HD-capable video camcorder and front-facing 1.3MP camera, superfast Snapdragon processor so navigation on the phone is quicker and apps load faster, 4.3” touchscreen for a great multimedia experience and 3G/4G capability. The combination of features and services on the HTC EVO 4G provide capabilities that were never previously available on a wireless device so customers will have a better experience and higher data usage on both the Sprint 3G Network and Sprint 4G Network.

Does having a faster processor mean that users will go through more data? Maybe, but not necessarily. Does having a kickstand and a large touchscreen mean that users will automatically go through more data than customer with other shiny new smartphones? No.

But never from the mysterious nature of the fee, Sprint also hasn’t been clear with consumers on whether they’ll need to pay the fee at all–which brings us back to the question of what the fee is actually for.

Reader Sean wrote earlier this week:

When I called the Sprint sales department asking about the Evo we checked where I live to see if 4G was available. It was not. Not even close. The sales person told me that I could opt out of the $10.00 premium data charge but if I went to a 4G area I would be limited to 3G because I did not enroll in the premium data package.

Once I bought the phone and checked my plan at sprint.com lo and behold I see the premium data charge. When I purchased the phone the girl behind the counter told me she was disabling 4g so I would not see the 10 dollar charge. I called support just now and had to speak to a supervisor. The super told me that the 10 dollar premium data was because of the 1ghz Snapdragon processor. What kind of web of lies is this? The Incredible, Nexus One, HD2 and other phones have a 1ghz Snapdragon and they don’t get hit with a “premium data” charge.

So, Sprint, can you explain in plain English, and not in circular marketingspeak, what the $10 fee is for? Is it for having the same processor that other phones on the market have? Is it for having a large touchscreen, like other phones on the market have? Or is it to help pay for the 4G network that the customers switching to Sprint because of the EVO have been promised?

You know where to find us, if you do have a straight answer.

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