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I've wanted a modded 3ds for a while but never got around to it since it sounded complicated. I found this listing on AliExpress and it has rekindled my desire I guess haha. But I want to research this first so I am once again asking Reddit some random questions. (I added photos of listing just in case information is needed?)

1.) how does the card reader thing work? Where does the SD thing go? Can I still put in game cartridges whilst all of this is booted on?

2.) could I add games myself?

3.) could I find it cheaper/do it better elsewhere?

I'm assuming this is the sub for this sort of thing? Sorry otherwise. Also sorry this is kinda stupid haha I'm not very tech savvy