Gateway-3ds is world first flashcard to support multi-3DS games.
World's first 3DS Flashcard for multi-3DS ROMs
Gateway-3ds was released on Aug 8th, 2013 as World's First 3DS Flashcard! It is one of two cards which are still of tech update support while those clone cards - 3DSLink, R4i Gold Deluxe & MT card are consequently dead.
Gateway-3ds flashcards are provided officially with a blue GW3DS and a red GW3DS as shown above. Blue GW3DS is used as a guide cartridge, while red GW3DS can only be used on 3DS / 3DS XL with systems below.
Only red GW3DS can play backup 3DS ROMs, blue GW3DS runs installation program and DS homebrew on other consoles (Other r4 card can also runs that GW_INSTALL.nds installation file, therefore blue GW3DS is not necessary).
If your 3DS is in higher system version, do not buy gateway 3ds and then there is only one card left to run 3DS ROMs - Sky3ds. If your 3DS is in lower system version, you can still update your console system into any one of 5 versions above. Do NOT wifi your 3DS directly, but to use original 3DS cartridge to force system update.
Which 3DS games can safely force 3DS system update ?
Please refer to games list updated by Ris32.
1x Red gateway 3ds chip
1x Blue gateway 3ds chip