R4 cartridge or R4i Card or other varieties such as R4 Revolution are the devices
for the Nintendo DS or Nintendo DS LITE and DSI version that acquiesce one to play games, listen to music, read books as well as explore world of other possibilities. R4i Card has the same size as that of a sanctioned Nintendo DS cartridge. It also has a slot at the back for insertion of a micro SD card so as to allow garnering music, movies and other applications such as firmware and other games according to your choice.
When one inserts a new Micro SD card into the R4 cartridge then on booting the machine one gets a menu so as to choose between games or multimedia that is socked away in the SD card. After R4i Card one can also push on to play home-brew games or other backup games or even listen to music or watch movies, all in the same Nintendo. All this is possible just by renovating the card. Below is a detailed history about the R4i Card.
The R4 cartridge was incipiently manufactured by the R4i Card team, who produced the first ever Nintendo DS R4 card in 2007. It also had a small slot at the top so as to push a Micro Secure Digital card inside. R4i Card came with a spring contrivance that would push the card into the slot, while the second push would bring out the card from its place. But this genre of R4i Card or cartridges with the spring apparatus was found to be faulty to the extent of 5%. The spring problem made the card to get dismantled. However if you want a cheaper card which is going to transact at a very high level the R4i Card will be enough for you.