3DS:Export saves

Save data is, for most people, the most important thing that exists on the 3DS. While games can be re-downloaded from the Nintendo eShop and homebrew applications can be re-downloaded from the open Internet, save files are one of the user-generated things that cannot always be replicated in the event of catastrophic failure. It is therefore natural for those who have the means to want to back up their save data in some way.

The Nintendo 3DS stores save data in the following ways:
 * Cartridges usually have a place on the cartridge itself to save their data. This means that a cartridge's save data will remain when the cartridge is used on another 3DS.
 * There are a few exceptions to this. Such games will save as "extdata" (extra data) and will follow the same rules as digital games.
 * Digital games save their data into a packed, encrypted format within the  folder. This means that in order to use your save data on another 3DS, you would need to unpack and decrypt it.
 * Cartridges and digital games save less important data (for example, Pokémon battle videos and Super Smash Bros. replays) as "extdata" in a packed, encrypted format within the  folder. Like the save data for digital games, you would need to unpack and decrypt it in order to import it to another 3DS.

With this in mind, there are many ways to export your save files into a format that:
 * Can be copied to many locations (e.g. computer, online storage, external hard drive)
 * Can be used for save file editing (e.g. PKHeX, Marc Robledo's ACNL Save Editor)
 * Can be used on another 3DS, or on Citra

= Cartridges =

Since your cartridge save data is (generally) on the cartridge, you can make your save data backups on any 3DS using homebrew applications.

(JKSM/Checkpoint stuff for cartridges)

= Digital games and extdata =

If your 3DS is working
If your 3DS is currently reasonably functional (as in, you can reasonably navigate through all the menus), you can make your save data backups on the 3DS itself using homebrew applications.

(JKSM/Checkpoint stuff for digital games/extdata)

If your 3DS isn't working
If your 3DS is currently nonfunctional (as in, you can't boot to home menu and the issue cannot be fixed), you may be able to make your save data backups depending on the files you have. You'll need any of the following:
 * Your NAND backup (e.g. )

If you don't have any of these files on hand, you may still be able to get your encryption key if:
 * It is cached on Bruteforce Movable (enter your Friend Code and ID0 combination to check; if it skips to Step 4 then you're good to go)
 * You have (physical or non-physical) access to a 3DS that has done a two-way friend exchange with your broken console at some point
 * You have a Mii QR code created with your broken console at some point
 * Your broken console can still access GodMode9, whether through a boot9strap installation or an ntrboot cartridge

Once you have your encryption key on hand, you can either:
 * Import the encryption key to a working console (from which you can use Checkpoint), or
 * Create unpacked, decrypted save data with the help of some computer programs

Import all SD card data to a working console
(manual movable transfer)

Use a computer to unpack and decrypt save files (easy)
(ninfs + 3ds-save-tool)

Use a computer to unpack and decrypt save files (hard)
(3ds-save-tool + secrets.py)