I've been using one for about a year now, and my wife has been using
one for just a little less time at her genealogy conferences (
http://themagikey.com ).  We've pushed through a chunk of money, and
it's worked well for us - no hassling with a merchant account or
dealing with a traditional credit card processor.

They sent me 100 units recently to pass along to others (they went
very quickly in my area - to the local tech and mobile development
groups). Also I ripped one apart.  It appears that it reads only one
track, and uses a single resistor, driving the microphone input to the
phone.

http://www.youtube.com/watch?v=3DhKSDs8XgOLA
Don't let anyone listen to your own credit cards, of course - use
other people's cards for that demonstration...

Here are my pictures of the unit I disassembled.  It's the most recent
version (Spring 2011) but I don't anticipate it's much different than
the earlier version I have been using.

http://www.flickr.com/photos/adavis/sets/72157627130260500/

One read head, one resistor, and a four pole audio jack with the read
head going to the microphone input and ground.

You can sign up for square and get one free, or buy one from the Apple
store, at least in the US.

-Adam

On Wed, Jul 6, 2011 at 3:26 AM, RussellMc <apptechnz@gmail.com> wrote:
> =A0 CCs: =A0Gavin - seen these ?
>
> These have been around since late early/late* 2010 in the US but I'd neve=
r
> heard of them until today.
> Probably totally passe to many list members.
>
> Credit card reader that plugs into iPhone audio in socket.
> Essentially given away as trojan horse.
> With one and tied in service anyone can accept credit card payments.
> 2.7% flat on transactions.
>
> * Some say announced 1 December 2009 and on sale Feb 2010.
> Others say actual service was launched in October 2010.
>
> It would be interesting to know how they get from card to iPhone internal=
s.
> I'd assume microcontroller in device reading 3 tracks as per normal and
> encoding them for audio transmission to iPhone.
>
> Apparently data is not encrypted.
> This can allow both a suitable application ion the iPhone to skim cards.
> This requires the user to be malicious.
> Better or worse, it can allow a "virus" to reside in the phone and to ski=
m
> cards and send data to persons unknown in eg =A0Ukraine, Nigeria, NZ etc.
>
> =A0As of March 2011 Verifone =A0were asking (who I know not) that the dev=
ices be
> recalled due to the lack of encryption. As Verifone market a competing
> (encrypted) service =A0and as most EFTPOS systems do not encrypt data at =
the
> reader, Verifone's motives have been questioned. Best of all is optional =
end
> to end encryption - an option generally not used.
>
>
> http://www.youtube.com/watch?v=3DsM2IN73LZaE
> http://www.wired.com/reviews/2010/02/pr_square_iphone
> http://www.iphonehacks.com/2011/04/apple-starts-selling-square-credit-car=
d-reader-for-iphone-ipad-ipod-touch-the-future-of-payments.html
> http://www.fastcompany.com/blog/kit-eaton/technomix/square-iphone-credit-=
card-reader-change-banking-game
> http://itunes.apple.com/us/app/square/id335393788?mt=3D8
> http://itunes.apple.com/us/app/square/id335393788?mt=3D8
> http://www.readwriteweb.com/start/2010/02/square-iphone-scanner-1-dollar.=
php
>
>
> Verifone seeks recall
>
> http://blogs.computerworld.com/17952/verifone_disclosure_of_gaping_flaw_i=
n_squares_card_readers_puzzling
> http://www.computerworld.com/s/article/9213924/VeriFone_seeks_recall_of_S=
quare_credit_card_readers_
>
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>
>

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