Here is a email from one customer, and some other customers also have the similar question.
Thank you for the reply and I am about to buy the card once I get my hand on the 3DS XL and I was wondering if there is any card that would run 3DS games? and also, when I use the card would those make my 3DS' warranty void?
Thank you in advance.
For the first question, whether the R4 3DS flashcart can play 3ds games on the 3ds. The answer is no. currently there is no 3ds flashcart can play 3DS games because 3ds haven't been hacked yet. so all the flashcarts will only let you play ds games on the 3ds without 3D function. But in future, when the 3ds real hacking is coming, there maybe a real 3ds flashcart can play 3ds games. but there is no ETA for it. so we can just wait.
For the second question, about the 3DS warranty problem. buy and use a flashcart on 3DS will not break the warranty, it won't leave any info on the console. But you need to remember take out the flashcart and sd card before you mail the 3ds to Nintendo.
And another similar question, would using a flashcart will block my 3ds console, no, there is no news confirmed that using a flashcart will brick a ds console, never happened before, so feel free to use them.