I am new to nitendo games,and just buy a 3ds console,i would like to buy an easiest card to play games,and read some news about ace3ds from the gbatemp,some players recommend this ace3ds flashcard,so i want to know whether this ace3ds card is the most easiest?Thanks for all guys in advance!
Despite its name, Ace3DS is actually a flashcart for the original DS(i); it can't play 3DS games (the "3DS" in its name simply means that it's compatible with newer 3DS updates that block other DS flashcarts).
That said, if you were actually looking for an original DS flashcart to use, they're all roughly the same in ease of use, you drag and drop the firmware files for your specific cart onto your microSD card, then just drag and drop games onto it and you're done.
If you were looking for actual 3DS flash cards, there are a few: Sky3DS+, Gateway3DS, and the upcoming Stargate3DS, but at this point in the 3DS's lifecycle, it's hard to recommend buying a 3DS flashcart for this console when CFW (custom firmware) has advanced to the point of being able to do everything flashcarts can (except for cheats, arguably), for free, or at a cost that's much lower than Sky/Gateway/Stargate.
Sky3DS+: You just drag and drop .3ds files onto this and it plays them without issue as long as your console is on the correct firmware version for the game (the game would prompt you for an update if you're not). Note that this can't play homebrew .3ds files or eShop releases converted into .3ds format without CFW (at least, to my knowledge).
Gateway: A card that lost support almost a year ago, it provides its own CFW that you boot into, and can run games off the flashcart. It provides a decently robust cheat system and can run homebrew .3ds files, eShop-format .3ds files. You drag and drop .3ds files onto its microSD card too, but you have to boot their CFW and push Select (or was it Start? Either way, it's a button press) on the Home Menu in order to bring the games list up. It also only works up to firmware 11.3 or so, which isn't the latest (if this has changed, correct me). Its CFW is also potentially dangerous to use if you don't know what you're doing.
Stargate3DS: This is kind of a Sky3DS+ 2.0, as it also brings DS flashcart functionality as well as can be used as a hacking tool for something called ntrboot, but it's really expensive (I think it's more expensive than both Gateway and Sky3DS+ at this point), as well as not being released yet (as of this post).
I would seriously recommend looking into using a CFW on the 3DS instead, if you're wanting to play 3DS games. It's really not any more complicated to install games in the CIA format (kind of like Wii wads) than .3ds files and there are applications out there that can download clean games directly for you. CFW also has additional advantages over 3DS flashcarts like being able to update to the latest firmware safely without fear (there's always a chance Sky3DS+ and Stargate could be blocked if Nintendo put in the effort to try and detect them), game mods, and running homebrew (Sky3DS+ and Stargate aren't going to be running homebrew unless you install a CFW).
Sorry for the long post, but the information given in the first post kind of needed me to cover both sides.