Some developers in Ireland have come up with an alternative solution. The R4 3DS card is an SD memory card packed with games that works with a DS adapter.
The developers took a similar approach to create the Sky3ds+ for 3DS games. The card works with 3DS ROMs and firmware downloaded from online sources to back up games that you already own. The ROMs are are stored in the root of a formatted SD memory card.
The Sky3ds+ costs 85,60 €.
For a closer look at how the memory cards work, check out the video below.