I got a Softbank M201 LTE (known as Motorola Razr M) phone from my company. As the screen is small, the phone is locked and cannot be unlocked yet, I wanted to use the SIM card in my Samsung Galaxy S4 (international) phone.
The S4 is an LTE capable phone and it works with the Softbank LTE network.
But the problem was the APN settings. On the M201 I could read the APN settings, but of course I could not see the required username and password.
A research on the internet (in Japanese) didn’t find anything until now. But luckily some Japanese guys(/girls?) found now a solution.
I found a guide how to extract the username and password from the Softbank M201 LTE on this website. It is about the Nexus 5 and M201 , but the guide can be used for other phone combinations. As it is in Japanese and on top using a special Japanese font that cannot be displayed by non-Japanese browsers I decided to post the guide in English.
Download Sbm4GSimInfo, unpack the zip file and install it on the M201 phone.
Have the Softbank SIM card in the M201 phone and start the Sbm4GSimInfo application.
It will show you the username and password for your SIM card.
Write down the username and password.
Move the Softbank SIM card to your LTE capable phone and boot it.
Goto Settings->WIRELESS&NETWORKS->More…->Mobile networks->Access Point Names (this path can be different, depending on the Android version of your phone)
Add a new APN with the following entries:
|Username:||<insert here the username that Sbm4GSimInfo showed you on the Softbank phone>|
|Password:||<insert here the password that Sbm4GSimInfo showed you on the Softbank phone>|
|Authentification type:||PAP or CHAP|
|APN type:||default, mms, supl, hipri|
|APN roaming protocol: IPv4||IPv4|
Make sure you save the entries.
Go back to the APNs screen, make sure you have selected the Softbank(4G) entry and wait a few seconds.
Now you should be able to use the Softbank LTE SIM card with the Unlimited Packet Discount Flat for SMARTPHONE on your international LTE phone.
All credits go to the (unknown) person who wrote the guide in Japanese and the (as well unknown) developers of Sbm4GSimInfo.apk