I just recieved mine I can not use it right now because I am wating for a microSD card that I got from Ebay to arrive but why does it come with two cartidges a black and a white one are they both exactly the same?
You can open the black cartridge and put the circuit board in the white cartridge - whch is useful if you have a White/Pink DS Lite, or for telling the difference between two units. I have a Black DS Lite and keep my M3DS in the black cartridge whereas my girlfriend has a Pink DS Lite so keeps hers in the white cartridge. It's competely cosmetic, there is no difference to how the unit works in either colour shell.
Think of it this way: you got one M3 DS Simply and two cases for the M3 DS Simply to go into. By default (at least how mine came in), the circuit board was placed inside the black case. Now, if you have a Pearl White DS and you want the M3 DS Simply to match it, you can unscrew the screw in the back of the black case, open the case, remove the circuit board, and then place the circuit board into the white case.
