Can you save with ReinMoon?

I've heard you can, if so, what about FF3? If so, how do you use it?

Reinmoon is only, I think, for DS CARTS. Not roms.

Reainmoon is an app that lets you save the SaveData from a DS card to you CF/SD/HDD whatever you have and then write it back.

Its handy for games that won't save patch so you have to use a donor card, it allows you to use just one or two donor cars for loads of roms.