Osaifu Keitai

Osaifu-Keitai (おサイフケータイ, Osaifu-Kētai^?), literally "Wallet Mobile", is the de facto standard mobile payment system in Japan. Osaifu-Keitai services include electronic money, identity card, loyalty card, fare collection of public transits (including railways, buses, and airplanes), or credit card.

The system was developed by NTT DoCoMo but the system is also supported by other mobile phone operators. It uses Sony's Mobile FeliCa ICs.

FeliCa, developed by Sony, is the de facto standard technology used for Japanese smart cards. Many of these cards accept Osaifu-Keitai (Mobile FeliCa) system as well, or plan to accept it in future. Osaifu-Keitai can provide more convenient services than plastic FeliCa cards. For instance, it can automatically recharge itself via the Internet, or provide the latest information. It can also be used as a ticket for an airplane or an event, by downloading an electronic ticket. Unlike plastic cards, a single Osaifu-Keitai phone may accept multiple applications, each equivalent to different cards.

Osaifu-Keitai provides many functions on a single mobile phone. Therefore, there is a great risk if the phone is lost, broken, or stolen. Osaifu-Keitai basically functions even without radio transmissions, so the applications can not be terminated just by closing a phone account. A user has to contact each service provider to stop all the functions. There are some phones that can lock the functions via a phone call or an E-mail.

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Wikipedia