DoCoMo To Unlock Devices From Its Network. Will Others Follow?

Japanese wireless provider NTT DoCoMo will allow customers to easily switch handsets and even take their phones to other carriers by inserting a different SIM card beginning next April, according to TeleGeography. The research service reported that the carrier will unlock handsets tied to its network and will include SIM-unlock software on its phones. Such a move essentially removes the carrier lock that ties a phone to a network, but for full customer freedom in Japan, DoCoMo’s competitors would have to follow suit.

DoCoMo currently enjoys the largest subscriber base in Japan, serving 49.8 percent of all Japanese subscribers at the end of May. DoCoMo says EMOBILE holds 28.3 percent, SoftBank has 19.7 percent and KDDI/au rounds out the group with 2.2 percent of the market. Even though SoftBank has fewer than half of DoCoMo’s subscribers, the carrier has one advantage: Apple’s iPhone. The phone (s aapl) is SIM-locked to work exclusively on SoftBank’s network, a scenario that’s unlikely to change in the near future.

Here in the U.S., the unlocked phone market stays small because of the huge amount of subsidized (that is, locked to a network) hardware. And even if the model were to change, consumers wouldn’t have total freedom, due to differing network implementations. With AT&T (s t) and T-Mobile, we only have two GSM providers to use with an unlocked handset. And then there’s the frequency variances — while I can swap my T-Mobile SIM with one for AT&T in my Nexus One (s goog), the phone would lose speedy 3G service because the phone uses the 1700 MHz band for HSPA, which is specific to T-Mobile’s service. For this reason, even an unlocked AT&T iPhone in the U.S. will only have slow EDGE data speeds on T-Mobile’s network.

A more open future here in the U.S. may be arriving with LTE, however. Both AT&T and Verizon (s vz) — the two largest U.S. carriers — will implement LTE with 700 MHz spectrum. Although LTE will initially be used solely for data, eventually voice will be piped over the network, which opens up the possibility of handset swapping between the two if they follow DoCoMo’s lead.

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