For all Nintendo 3DS users, SD card is really important because it saves a great amount of data that can affect the device's operation For example, DLC (downloadable contents), the system update files, the contacts with friends, the games downloaded from Nintendo eShop, the builtin software, the pictures captured by 3DS, all of them are saved in the SD card by defaultSelect Disk Management from the left corner of the list displayed; The answer is you can change SD cards as long as you are willing to move the data to your new card, and you will not lose any data Here is a link to the official nintendo guide to migrating SD cards You just have to copy stuff over Also make sure your new card is formatted as FAT32, or you could just use your 3DS to format it
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