"Nintendo DS storage devices are some of the devices used to store a licensed developer's work-in-progress images, homebrew video games, or downloaded commercial games, since the Nintendo DS is not sold with a rewritable storage medium. (Licensed developers can use the blue Intelligent Systems Nitro Emulator box to flash cards.) There are two main classes of storage devices: older devices that fit in SLOT-2 (the Game Boy Advance Game Pak slot) and newer devices that fit in SLOT-1 (the DS Game Card slot). SLOT-2, or 1st generation, devices have historically been cheaper due to economies of scale inherited from their use with Game Boy Advance homebrew but require a booting tool in SLOT-1 in order to use the touch screen and other DS features. Devices that only use SLOT-1, or 2nd generation, do not work with GBA homebrew, but as of 2007[update], they are becoming easier to use and less expensive, rivaling many SLOT-2 devices in price which may have been cheaper."
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