Osaifu-Keitai

Osaifu-Keitai (おサイフケータイ), which means "Wallet Mobile", is the 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 term "Osaifu-Keitai" itself is a registered trademark of NTT Docomo.

The system was developed by NTT Docomo who released it to the public in 2004 but the system is also supported by other mobile phone operators. It uses Sony's Mobile FeliCa ICs.

Operators

 * NTT docomo Group: i-mode FeliCa
 * KDDI (au/Okinawa Cellular): EZ FeliCa
 * SoftBank Mobile: S! FeliCa
 * Willcom: WILLCOM IC Service

Advantages
FeliCa, developed by Sony, is the 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.

Disadvantages
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.

Since Osaifu-Keitai can function as identity card (such as member card, company card, or keycard), there is also a risk for those who authenticate it.