Nintendo announced on February 21, 2006 that New Super Mario Bros. would launch for the Nintendo DS on May 7, 2006. The game's new power-ups were also introduced at the same time, including the Blue Koopa Shell and the Mega Mushroom. Nintendo further mentioned that the game would be played in 2D but use 3D models to create a 2.5D look and feel.[1][2] The May 7 release was later delayed towards May 21, but the game's release date was eventually pushed back slightly to May 15; Nintendo also planned to release it around the same time that the Nintendo DS Lite launched, on June 11, 2006.[10]

New Super Mario Bros. is the first 2D platform game to star Mario since Super Mario Advance 4 in 2003.[4] First revealed at the 2004 E3 convention,[11] New Super Mario Bros. was available for play at E3 in 2005. The game's designers were given much more freedom with designs in New Super Mario Bros. compared to previous 2D Mario games. Characters, enemies, and objects could now be created with much more detailed animations, without requiring that they be designed by hand. To provide visual cues, the developers made the game's camera more dynamic; it zooms in and out of action depending on the situation to provide focus where necessary.[12]

Physics play an important role in New Super Mario Bros.'s improved game mechanics. Without the rigid restrictions of tile-based sprites and backgrounds, the designers were free to explore new gameplay mechanics; when Mario lands on top of a tree, it teeters over and eventually falls if he is stationary for too long. Mario can also swing on ropes and walk on wires that bend and stretch under his weight.[12]

Early in the game's development, the developers planned not to use voice acting to stay true to the spirit of the original Super Mario Bros. However, voice acting was eventually embraced by