Web-based POS used by local hardware chain

While doing some improvements on the McGill Outdoors Club house up in Prevost, QC, we stopped at a local hardware store called "Matério". They're a chain in Quebec.

While standing in the checkout line, I became curious (as usual) about how their Point of Sale (POS) system worked. I snuck a peak at the touchscreens...

I could see that they were doing the entire sale in an IE window, with an internal  192.168.x.x URL. Every item that was scanned populated the webpage after a brief auto refresh.

Custom or Open Source?

The interface was all French, leading me to believe that this was a custom job written for them. But what a great idea! I would think that all POS systems should be web-based. This way your terminal manufacturer and OS are moot, as long as a web browser is available, you can process sales

UI Design

Couldn't help but notice that on the payment page (final page of a sale), there were about 5 fields stacked on each other, each field labeled for a method of payment (Interac, Credit, Cheque, Cash), but to get to the "Cash" field at the bottom, the cashier had to use the scroll bar on the right and drag to reveal the lower fields.

As a wannabe UI designer I surmised a couple of things:

1. Page should fit on screen without scrolling, this is a design flaw
2. IE should be running full screen without the address bar to save space--I shouldn't be seeing the URL at the top, it's a waste of space.

Some other possible snafus

Of course, a web-based PoS could have a few hurdles to get over.

1. If there is a mag-stripe reader, how do you give focus to the correct field in the webpage without having the user tap to put the cursor there first? Is there a backchannel you can use to interface with the stripe reader rather than emulating an input device?
2. Printer needs to be networked to the main server (serial-over-IP), as we can't guarantee that every terminal/PC using the PoS can reliably print to a local receipt printer.

Another establishment in my area, called Le Next Door, on Sherbrooke and Marlowe, has a custom built app based on Access it looks like. I spoke to the owner briefly about it (he wrote it, he's a CS grad), and from what little I can tell it's pretty simple to write POS software this way as a "native" application. He runs it on an ASUS all-in-one machine. Has a keyboard and mouse attached to it, which means it's not quite finished, in my opinion all functions should be available by touch screen.