NTT DoCoMo will begin selling three mobile phones in May that offer motion sensitive gaming like that possible with Nintendo's Wii games console.
In a boxing game, users can throw punches or duck, and their movements are picked up by the phone's camera. In another game, the phone can be tilted in different directions to guide an on-screen ball through a maze.
"Traditionally, in trains youngsters would be staring down at their phones playing games but that is going to change dramatically," said Takeshi Natsuno, senior vice president of NTT DoCoMo. He was speaking on Monday at a Tokyo news conference held to unveil the phones, raising the prospect of people on trains getting much more animated as they attempt to respond to on-screen challengers.
To be sure, the mobile phones aren't nearly as reactive as the Wii console but they are likely to become more so as technology improves.
The gaming handsets are made by Mitsubishi, Panasonic and Sharp and with two other models make up the first five in the carrier's 904i-series of phones.
With the new range NTT DoCoMo is hoping to hit back at its competitors and recover some of the ground lost since the introduction of mobile phone number portability in Japan last year.
"DoCoMo is going to take the offensive," said Natsuno. "We are going to offer various things that cannot be mimicked by the other operators."
Alongside the motion-sensitive gaming, NTT DoCoMo will launch an all-you-can-eat music download service with Napster that allows users to download and listen to any music available though the Japanese version of the Napster portal. Users will also be able to get a second phone line and e-mail address on a phone for ¥945 (£4) per month.
The new phones, all of which are WCDMA (wideband code division multiple access) 3G handsets, will go on sale in Japan in May and June. They won't be available in other countries.