As a child, he spent time creating flip book-style animations in the corner of text books and making motor-driven mechanical toys, since these were the only technologies available to him.

[3][4] His 1985 installation Time Stratum won the Gold prize at the High Technology Art Exhibition '85, held in Shibuya Seibu, Tokyo.

[1] In 1991-92 Iwai was an Artist-in-Residence at the Exploratorium in San Francisco, California, where he created two exhibits that are now part of the museum's permanent collection, Well of Lights (1992) and Music Insects (1992).

[7] Iwai is the first internationally recognized gallery artist also to have led the creation of several successful commercial video game projects.

[11] Iwai's first game was the musical shoot 'em up Otocky (1987), produced in association with ASCII Corporation for the Famicom Disk System, an add-on for the NES available only in Japan.

Otocky is a precursor of Rez, Tetsuya Mizuguchi's 2002 Dreamcast and PlayStation 2 game exploring similar themes of player action and musical evolution.

The player can select colors from a palette and paint on the grid, triggering new results and changing the insects' direction, improvising a visual music performance.

[14] However, the game's release was cancelled and it was eventually converted into the PC title SimTunes, published by Maxis, a division of Electronic Arts.

[1][15] In 2000, Iwai worked to publish Bikkuri Mouse (びっくりマウス), a collaborative drawing game that became the PlayStation 2's first mouse-compatible title.

[18] A suite of ten different interactive music and audio toys themed around cartoon plankton and using the novel touchscreen and microphone interface features of the Nintendo DS, Electroplankton draws heavily on Iwai's earlier work, including Composition on the Table.

[19] In 1990 Iwai's solo show Machine for Trinity exhibited at the Laforet Museum in Tokyo; some of the works shown there demonstrated that computer graphics could be generated and combined in real-time with live action images.

The performance included use of Iwai's installation Piano - As Image Media and a version of Resonance of 4 adapted to use a chessboard-like interface.

[8] In June 2004, Iwai gave a prestigious invited public lecture at the 4th International Conference on New Interfaces for Musical Expression, held in Hamamatsu, Japan.

Called Tenori-on, the instrument is a sixteen-by-sixteen array of illuminated LED switches which can be activated in a variety of ways to create a changing musical soundscape.

[26] Installations Permanent Exhibits Videogames Television Performance Digital Musical Instrument Design Books, magazines and printed matters Others