Heres a dev tool app for the Nintendo DS:

GamEditorDS is a collection of developer tools for game-making on and for the Nintendo DS including content uploader, level-, sprite- and animation editors along with a 2D game engine supporting sound/music. If you are interested in getting Nintendo DS development startet, mabye this is for you!

via https://pdroms.de/nintendods/gamedit...04-30-nds-misc