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OCN Mobile One

OCN is an MVNO (reseller) of Docomo service, and Mobile One is their most recent branded service.  What makes Mobile One unique is that OCN is a subsidiary of the same group (NTT) as Docomo.  So they are in effect competing against themselves.  

SIM Types:
  • Data only SIM : This is the cheapest type of SIM card.  It will work in any kind of device, but is especially suited for routers and other devices that can't use other features anyway.
  • SMS enabled SIM: This is good for smart phones where native voice is not needed.  (You can always get voice through VOIP applications like 050+).  SMS is a big deal for some people, since it is required to sign up with some services that require SMS verification, such as Line.
  • Voice capable SIM: This type of SIM card is the most recent addition, and allows the placing and receiving of native cell phone calls. (Obviously this type of card is only useful for phones).  
Contract Considerations
  • It is important to note that due to legal restrictions, the sign-up procedure for the voice enabled SIM is more strict than the other forms. (You should submit ID to prove that you are a Japanese resident).
  • The voice enabled SIM card has a minimum usage contract period of a year.  This is to prevent people from playing games with the MNP kickbacks offered by the various carriers.  (This contract is not auto-renewed, and the service may be cancelled at any time after the contract period without incurring any termination charge).
  • OCN also offers device rental.  If you decide to rent a device, such as a WiFi router, from OCN, then there may be a 1 or 2 year contract.
  • You can buy the SIM cards in the store and then activate online, or you can sign-up online and OCN will main you the SIM card.
Mobile One and 050+
Although it should be noted that you can of course use any VOIP application (Skype, LaLa Call, etc.) over Mobile One, 050+ is discounted for the data SIMs, and included for free with the voice capable SIM plans.  Although the basic rate is cheap, the rates for outgoing native calling from the voice capable SIM are high (the same as undiscounted Docomo rates), so it makes more sense to use the 050+ functionality for outgoing calls where possible.  What's more, 050+ can be used from overseas in most companies without paying a roaming fee.  

Special Features
While the service is pretty basic, there are a few special features
  • You can share the same data plan among several SIM cards, so that you don't have to pay twice as much to have two devices.  Each SIM card costs a small additional fee.
  • There is an application which can be used to track your data usage, and enable/disable "turbo mode" (full speed mode).  You can turn turbo off in order to make sure you don't accidentally go through your data too quickly.The application can also show you how much data was used on the device you are using at the moment vs. the other devices.
Plan Fee Basics
  • Activation Fee: There is usually a 3000 jpy activation fee, though sometimes that is waived.  (Note that this fee is reduced to 1000 jpy for additional SIM cards).
  • Basic monthly Fee:  The basic fee differs by SIM card type, starting at around 900 yen for the data only card for the cheapest plan, to over 1600 yen for the voice capable sim on the cheapest plan.
  • There are three types of data plans:  Daily, Monthly, and Unlimited.
    • Daily Plans have a daily data limit, after which, transfer speed will drop to 256k for the rest of the day. (Note that 050+ calls still work fine with 256k speeds)
    • Monthly plans have a monthly data limit, after which transfer speed will drop to 256k for the rest of the month.
    • The unlimited plan always has 500kbps, but allows an unlimited amount of data at that speed.
    • Prepaid plans targeted at tourists are also available, however we won't discuss them here.
  • Other than the unlimited plan, all of the plans are LTE and have a maximum speed of 150Mbps until they reach their limit.
  • Recently, OCN started a new data roll-over feature to all customer, where unused data from one period is rolled over to the next.  This means that for the daily plans, unused data can be used the next day.  Likewise, for the monthly plans, unused data can be used the next month.  (This feature was added to all customer accounts automatically).
  • OCN has raised the data limits already in the past, but is raising them again, effective 2015/4/1.  For example, the current daily 70MB plan will change to 100MB, and the current monthly 4GB plan will change to 5GB.  It's hard to argue with extra data for the same price!
  • The data plans are the same, regardless of SIM type.
Additional Data
If and when you run out of data, your connection rate will be throttled to 256k, which is probably fine for most smart phone usage.  If, however, you want to increase the amount of data and restore your connection to full speed, you can purchase additional data online or from within the Mobile One application.  Basically speaking, it works like this:
  • Monthly Plans: 0.5 GB for 500 yen
  • Daily Plans: Unlimited for the day for 500 yen
The unlimited one day pass is a good deal for those who will use the data only chat and browsing on their phone on most days, but occasionally want to tether data to their computer on the weekends.  

Other Fees:
Although Mobile One is basically a flat rate data service, other fees can add up:
  • SMS fees on the SMS enabled SIM cards.
  • Outgoing call fees on the voice enabled SIM cards.
  • Additional SIM card fees if you have more than one SIM card on the same data plan (450 jpy per month).
  • Outgoing call fees for 050+ if you use this service to call other non 050 numbers.
  • Additional data fees if you decide to purchase additional data.
  • Additional device rental fees, should you choose to rent a device such as router from OCN.

Although the information available in English is sparse, please check the OCN Mobile One Official English Web Page for further information.