Luma3DS game patching
Luma3DS allows for the modification of a game or application without having to patch the original files. This is done by redirecting the reading of files to a separate location containing the modified files. Because no original game files are actually being modified, this feature works with physical game cartridges. To use this feature, files must be placed in a /luma/titles/<Title ID>/ folder. You can get the game's title ID from here (cartridges), here (digital games), or from the FBI -> Titles menu. For example the Title ID for Pokémon X is 0004000000055D00, so modified Pokémon X files would be placed at /luma/titles/0004000000055D00/.
External code.bin and exheader.bin loading
Patched code.bin and exheader.bin files can be loaded. Compressed .code files will not work with this feature, it must be uncompressed into a code.bin.
IPS patching
IPS patches for code.bin are also supported, which contain only the changes to the original code rather than the entire code.bin. Patches should be named code.ips and placed instead of a patched code.bin.
LayeredFS
Files within a game or applications romfs folder can redirected by placing modified files within /luma/titles/<Title ID>/romfs.
Locale Emulation
Plugins
CTRPluginFramework 3GX - Blank Template
MegaNTR PLG plugin collection
Plugins list from gamebrew
Cheats
CTRPluginFramework Action Replay cheat codes
Save editors
ROM editors
External links
Luma3DS/wiki/Optional-features
List of Rom Hacks from gamebrew
save editor 3DS applications from gamebrew