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AT&T iPhone/Mobile Tethered Users Beware: One Gigabyte of Wireless Bandwidth: $503.00

Posted by Keith Elder | Posted in Apple, Mobile Devices | Posted on 16-11-2008

imageAT&T recently announced they were going to support tethering for the iPhone.  I am sure a lot of users are happy about this move, I know I am as that has been the one thing that has stopped me from not getting an iPhone and to this day is why I continue to use my Blackjack II.  This announcement, coupled with a reader commenting on a previous article about whether I would recommend tethering the Blackjack II if someone traveled 70% of the time, got my curiosity up.  Thus I started to dig in. 

To answer the comment from the reader, in my opinion, that much travel would warrant more of a dedicated device.  Curious I went over to the AT&T web site to check out the AT&T USBConnect Mercury device they’ve been advertising for months now.  You know the one, the one that Bill Kurtis finds the Internet with?

Right now the device is free after mail-in rebate. Here is a screen shot for posterity sakes.


If you walk through the shopping cart the next thing you have to do is add a data plan.  Currently only one plan is available and the monthly cost today is $60 / month which gives you 5GB of data. 

Currently AT&T offers a tethering option for phones like the Blackjack II and others.  Both the tethering data plan and the USBConnect Mercury use the same calculations, 5GB to start with and then so much for additional data.

Pay Attention!

Ok, here is the kicker to this that a lot of people probably won’t pay attention to.  The additional data cost is:


Here’s a snapshot of the value from AT&T’s web site (for posterity):


Someone may read this and go, cool, that sounds really cheap.  There are a lot of zeros in there.  But don’t be fooled!

The key here is they measure cost in terms of KB (kilobytes).  For those that don’t know how this works, there are 1,024 bytes in a Kilobyte.  To put this into perspective, if you visit the home page of http://www.amazon.com, you will download roughly 300KB to load the page.  As you can see, this is a really low level of measurement, really we can only go one step lower and that is to just measure bytes.  

There are 1024KB in a Megabyte and 1024MB in a Gigabyte.  Thus our formula for calculating how much it would cost a consumer that downloaded an extra GB (gigabyte) of data during the month by either tethering an iPhone or using the USBConnect Mercury is as follows:

1024(KB) = 1MB
1024(MB) = 1GB
Cost per KB:  $0.00048

1024 * 1024 * .00048 = $503.31


$12/GB for First 5GB, and then $503/GB After That

Can you just say wow?  I couldn’t believe this when I added this up.  I was in so much disbelief I had a few programmer buddies calculate this as well. 

It would make more sense logically speaking for AT&T to say they gave you 5GB at $60.00, and then if you use another GB, then it is going to be $11.99.  But that would be too easy to calculate.  For some reason AT&T thinks they can justify charging $503 for one GB of wireless data, yet sell you others at $12 a GB. 

For those that are thinking they can use their iPhone any and everywhere as much as they want, seriously, be careful!  These words of wisdom aren’t just for iPhone users, but for anyone tethering a device to AT&T’s network like the USBConnect Mercury or other mobile phones that is a heavy user and traveler. 

Comments (3)

@Joe (fixed, thanks)


Trust me, I am sure other companies are just as guilty. I wasn’t trying to single out AT&T but that is who sells the iPhone which just announced tethering is coming. Also AT&T is who I use today with my Blackjack II.

Although I don’t agree with it, it seems unfair to single out AT&T here as all cellular companies I know of are like this. For example, in the UK O2 charge £0.20 per MB so that works out as £204.80 ($304) per GB. It’s wrong but all the cellular companies get away with it. It seems all too common.

@Keith – Your calculation text is incorrect, although the end value is correct. You show 1024 * 1024 * .0048 which should be .00048. I have always felt that wireless companies screwed over users who try to use a tethered phone. AT&T has long been the worst offender.

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