I was wondering because I wanted to play Phantom Hourglass and Tomodachi Collection. (I lost the cardtridge to PH and I dont want to import TC)
No there isn't. You could try using TWLoader and nds-bootstrap, but it has somewhat low compatibility.
Couldn't tell you how, but I'm pretty sure there's a way to make a forwarder. When the bootstrap gets to the point where it can run the games you want adequately you may want to check into that. EDIT: https://gbatemp.net/threads/nds-bootstrap-loader-run-commercial-nds-backups-from-an-sd-card.454323/ https://gbatemp.net/threads/nds-forwarder-cias-for-your-home-menu.426174/ I believe that's it.
no. this is because we cant convert them, because in the original NDS, all system calls were directed to the slot, because dlc games didnt exist yet. essentialy this would require forwarding all system calls to the sdcard, including saving, which we currently are VERY limited to doing. converting them to cia would also mean editing them to run on 3ds hardware (to be boot from the home menu) so other then flashcard, there is no reliable way to run nds games.
iirc forwarders only forward to a flashcard. And as discussed before the nds bootstrap loader is very low compatibility. I would just invest like $15-20 USD for a decent flashcard like the r4i gold 3ds. It's really not that much to invest for opening the door to play basically every DS game.
The link I posted lists an option to create one from a ROM on the SD card and links to the bootloader compatibility list; I haven't really looked into it or tried it. I assume it uses something like TWL_Loader in the process of making the forwarder. Come to think of it, TWL_Loader has an option to launch ROMs from a flashcart, so I wouldn't be surprised if it did use TWL_Loader in some way.
That's not technically what OP wants though. It still has to run from either a flashcard, which costs money, or the NDS Bootstrap Loader (which is probably what you are referring to), which has very limited compatibility. At this point flashcard is still the way to go, and as others have stated they are dirt cheap anyway.
Still, I'm fairly certain the NDS bootstrap loader is very limited in what it actually supports last time I checked, so really unless you only want to play a few DS games the flashcard is the much better option anyway.
