R4DS

The Revolution for DS (most known as R4DS or simply R4) is a series of flash cartridges for the Nintendo DS handheld system. It allows ROMs to be booted on the Nintendo DS handheld system from a microSD card. This allows the user to run homebrew applications, to store multiple games on a single memory card, and to play games that have been backed up by the user. The R4 flashcard's original developer stopped producing the R4 Card that plays ROMs for the Nintendo DS, however, there are a new line of R4 clones that have taken its place, notably the R4 3DS, R4 Gold, R4 DSi and R4 NES, which are used to play ROMs from various Nintendo platforms such as the Nintendo 3DS, Nintendo DSi, Nintendo DSi XL and Nintendo Entertainment System.

The original R4 cards use a microSD (<=2GB) card for its firmware and games, and does not support SDHC microSD cards. The original Revolution for DS cart is no longer available in stores, although it can be bought online. However, there are other carts that are of similar quality made by other entities that have adapted the name, commonly referred as 1:1 clones. These are flash carts that use exactly the same hardware and are, for all intents and purposes, also referred to as the original R4 revolution. However, they often include SDHC support and other small changes and add-ons that make them different to the original R4 cards.

The R4 flash cartridges are banned in most countries due to copyright infringement lawsuits from Nintendo. In late 2007, Nintendo began a legal crackdown with a series of raids against R4 merchants.

In 2010, the company Playables Limited, importers of R4 flashcarts, was ruled against by the London High Court. The ruling outlawed any sales, importation, or advertising of the R4 flashcarts. The defence of Playables Limited claimed that the R4 flashcarts were legal because it uses a homebrew application. However, bypassing Nintendo’s security system is against the law in the United Kingdom. After the news broke, Nintendo released on a statement saying that they do support game developers that create their own applications legitimately. 100,000 copying devices including R4s were seized in 2009. Nintendo claimed that the carts were not only seized for the benefit of their own company, but the benefit for over 1400 video game companies that depend on the sales of their games.

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