Link
It is unknown what this cartridge does. All the known copies were said to be nonworking and the DS does not recognize the cartridge when it is inserted into the system.Â
First off, what is Nintendo Zone? Basically auto WiFi connection points authorized by Nintendo.
Bring your Nintendo 3DS system to any of over 29,000 locations to receive an automatic and free connection to Wi-Fi. Once connected, discover Nintendo Zone: watch 3D videos, full length animations and sports highlights, play demos and trivia challenges, find retailer promotions and coupons – and much more! To get started, tap the blinking Nintendo Zone icon on the HOME Menu of your Nintendo 3DS system.
I’m cobbling stuff together here from various forum threads, so hopefully someone with more dev experience can chime in.  Some people report that the Nintendo Zone point has been running off a DSi-XL , which had a DS cart locked into the system. Other posts make references to the device at the left, which is apparently hooked to a laptop.
I’m guessing this cart is from one or both of those scenarios. Either way, cool cart and the first time I have seen one listed.
Seller also has two non working Nintendo DS Test Debug Cartridges marked Wireless Test and NTR Audible Button Test.
i’ve a picture of Working Nintendo Zone, & it’s not the picture below ^^
http://www.1038.fr/wp-content/gallery/japan-expo-2012-2d/dscf8688.jpg
inside, you have a DS lite !
I know why all this weird set-up is needed, you can do it anywhere with any routers by changing the SSID to attwifi and making it an unsecured connection
you need this box & wifi router with correct SSID and no secure for a nintendo zone.
Maybe for the DSiWare Nintendo Zone, but what I said earlier is a trick that works for real with any routers. Confirmed to work on 3DS at least