Nintendo is slashing the price of its 3DS as it prepares for a fresh lineup of games. (KIYOSHI OTA/BLOOMBERG)

The 3DS — which displays 3D graphics without the need for glasses — has seen lukewarm sales since its March release. An underwhelming opening lineup of games and its high price were both named as barriers to customer interest.

The company is also facing an industry shift toward casual smartphone gaming. John Riccitello, chief executive of game giant Electronic Arts, said at a conference Wednesday that the iPad is the company’s fastest-growing gaming platform, TUAW reported.

Did you buy a 3DS at its higher price? Don’t worry, Nintendo hasn’t forgotten about you. The company is offering 20 free downloadable games to any 3DS owner — all you have to do is connect to the company’s eShop once before midnight Aug. 11 to register for the “3DS Ambassadors” program.

Those who register for this program will be able to download 10 classic Nintendo NES games, including “Super Mario Bros.,” “Donkey Kong Jr.” and “The Legend of Zelda” starting Sept. 1, before they go on sale to the general public. They’ll also have exclusive access to 10 Game Boy Advance games including “Yoshi’s Island” and “Metroid,” that the company says it has no plans to release to the general public. Players will be able to download those titles by the end of the year, Nintendo said.

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