During my time as a Bmobile customer, I've asked their helpdesk numerous questions regarding their mobile phone services. I share the questions and answers below.
Can I choose the phone number?
You cannot choose your phone number if you order the SIM card online. BMobile did say that you may have luck choosing a phone number if you buy the SIM card at a brick-and-mortar shop (e.g. Yodobashi Camera or Aeon) because you can see the phone number assigned to the SIM at the time of purchase. I went to Yodobashi Camera in Akihabara and asked about this. They said that I can't shuffle through all of their SIM cards in their stock room hunting for my desired phone number. Fair enough. However, I can give them a general request when purchasing the SIM. For example, I can request 090 or 070 or an easy-to-remember number. Other shops may have different policies. Or it may depend on something as trivial as how good a mood your clerk is in that day.
Can I change my phone number?
Yes, but you have to purchase a new SIM card package. You can't change the phone number assigned to your current SIM.
Can I keep my current phone number?
Yes, you can. Bmobile supports Japan's standard mobile number portability (MNP) procedure.
Can I change my plan & options later?
Yes, you can. Bmobile's customer console features options that allow you to change your data plan (e.g. 1GB / month --> 2GB/month) and voice calling options (e.g. international calls, voice mail, etc.).
Does phone X work with Bmobile? Does phone X get LTE?
Please refer to Bmobile's list: http://www.bmobile.ne.jp/devices/devices.html I asked Bmobile about this list, and they said that these are the phones they have actually hands-on tested. Could others work? Maybe, maybe not. Do you like that answer? Yeah, real professional, huh? You could buy a cheap data-only SIM and give it a try. Generally speaking, since Bmobile is re-selling NTT Docomo's service, phones that NTT Docomo sells and supports are a relatively safe bet.
Can I use a Blackberry?
You still have one of those?? I know. I know. You love that keyboard, huh? Ummm...sorry, but no. Blackberries don't work with Bmobile.
Is credit card the only accepted payment method? Can I pay via bank transfer or debit card?
Only credit card.
I don't have a Japanese credit card. Can I use an overseas credit card?
Yes, you can.
Can companies use Bmobile's service?
No, companies cannot apply.
A far more exhaustive FAQ (in Japanese) can be found here: http://www.bmobile.ne.jp/personal/faq.html
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