Mobile Suica

Mobile Suica (モバイルSuica, Mobairu Suika^?) is a service for Osaifu Keitai mobile phones, first launched on January 28, 2006 by NTT DoCoMo and au in Japan, and now also offered by SoftBank Mobile and Willcom.

Just like traditional Suica cards, which are prepaid rechargeable contactless smart card mainly used to pay for fares on the JR East railway network, Mobile Suica can also be charged when the remaining balance gets low. Other features supported by the mobile phone includes the ability to review past Suica transactions via the mobile's display. Suica uses Sony's FeliCa chip for its main functionalities. Mobile Suica interacts with the FeliCa chip using Java technology.

Since October 2006, it is possible to register for Mobile Suica using any major credit card, a Suica VIEW card is no longer required. A limited e-money only application called "Easy Mobile Suica" (which does not require a credit card) was also launched in late October 2006.

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Wikipedia