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Guide for Foreigners Can I Use My New Residence Card to Sign Up for Rakuten Mobile? Yes, the New Types Are Accepted
Rakuten Mobile now accepts the new residence cards issued from June 14, 2026, at shops, and online from September 1. Which cards, and what the notice does not say.
Guide for Foreigners Typhoon No. 18 Support from Rakuten Mobile: Free SIM Reissue, No ID at Shops, Later Payment (Apply by Oct 31, 2026)
Rakuten Mobile announced support measures after Typhoon No. 18 on Sept 30, 2026. Who is covered, what you get, and what you must do by October 31, based on the official notice only.
Guide for Foreigners Before Using a Phone or Tablet Bought Overseas in Japan: Checking the Giteki Mark, and a Real Case Where Only LTE Was Uncertified
Using a device without the Giteki mark in Japan may violate the Radio Act. How to check overseas or used phones, plus an Oct 2026 tablet lacking LTE certification.
Rakuten Mobile A Known Test Key in Boot Verification on Rakuten Mini, Hand, Hand 5G and BIG s: What JVN#47427200 Says, and What Owners Can Do
JVN (Oct 14, 2026): a known test key is used for boot verification on all versions of Rakuten Mini, Hand, Hand 5G and BIG s. Physical access required; gaps noted.
Rakuten Mobile Rakuten Mobile: Payment Certificates in "my Rakuten Mobile" Could Have Been Viewed by Third Parties. Sorting Out the October 13, 2026 Announcement
Rakuten Mobile said on Oct 13, 2026 that payment certificates could be viewed by third parties. What is confirmed, what is not written, and general tips.
Guide for Foreigners Got an SMS or Email Claiming to Be Rakuten Mobile? How to Check If It's Real, Even If You Can't Read Japanese
Steps for when a Japanese SMS or email says it's from Rakuten Mobile. Don't tap the link; check in the app or a bookmark. Never share passwords or codes. If unsure, call the official line (0800-600-6660) yourself (checked Oct 27, 2026)
Telecom Technology 4 Mobile Carriers and the JMSDF Okinawa Base Force Sign a Disaster Agreement: What Does Carrying Recovery Crews by Ship Mean?
Docomo, Okinawa Cellular, SoftBank and Rakuten Mobile signed an agreement with the JMSDF Okinawa Base Force on securing communications in disasters. Summarized per Keitai Watch, with preparations you can make.
Rakuten Mobile Rakuten Mobile Fees Overview: Contract Fee Starts from the 5th Cumulative Line; Cancellation, SIM Reissue and Payment Method Costs Checked
Rakuten Mobile's contract processing fee, cancellation fee, SIM/eSIM reissue, name change and payment-method costs, as far as the official pages confirm. How 'cumulative' is counted, and what is not written, are noted.
Telecom Technology What Your Phone's Signal Bars Really Mean: How to Read dBm and RSRP, and Rough Guidelines for the Numbers
Signal bars are only a rough guide, and the criteria differ by device. A general explanation of dBm, RSRP, RSRQ and SINR, and rough guidelines for the numbers.
Telecom Technology Full Bars but Slow or Dropping Connections at Stations and on Trains: The Cause Isn't Only 'Signal Strength'
The bars are up, yet the internet won't connect at stations or on trains. Causes include crowding, base station handovers while moving, and underground or tunnels. The mechanisms and quick fixes.
Telecom Technology SpaceX Buys 800MHz Spectrum in the US: Preparing for Phones That Connect Directly to Satellites, and Why 800MHz
SpaceX reportedly agreed to buy nationwide US 800MHz licenses for D2D (satellite-to-phone). Sorted out per Keitai Watch's report, plus why 800MHz matters.
Telecom Technology Is It True That Putting a Phone in a Box Makes It Untraceable, as Often Seen in Dramas? The Difference Between Signal Blocking and Jamming, and a Real Case of an Attack on Satellite Communications in 2022
Put a phone in a metal box and its location can no longer be tracked. Does that scene hold up in reality? I sorted out, within what I could confirm, how signals are blocked, how that differs from jamming and spoofing, and an actual attack on satellite communications in 2022.
Telecom Technology Calls Cutting Out or the Other Person Hard to Hear? Isolating the Cause Step by Step
When calls cut out, the voice is quiet or there's noise, we sort the causes into signal, device, connected equipment and apps. Also covers Rakuten Link's non-guaranteed conditions, within what the official page says.
Telecom Technology Can You Count on Your Phone in a Disaster? Five Things to Prepare in Advance
When your phone can fail in a disaster, and what you can prepare ahead of time: emergency numbers, the disaster message dial, battery, offline maps and how to decide on contact methods, as general ideas.
Telecom Technology How Does Your Phone Know Where You Are? The Division of Labor Among Satellites, Cell Towers, Wi-Fi and Bluetooth
The blue dot in a map app is the result of cross-checking satellites, cell towers, Wi-Fi, Bluetooth and sensors. We sort out each one's accuracy and strengths and weaknesses, following a Keitai Watch column.
Rakuten Economy Seeing Rakuten Mobile as a Tool for Using Rakuten Services, Not Just a Phone Line: How Much Does It Change Per Month? I Ran the Numbers, Including SPU, U-NEXT and YouTube Premium
If you spend 10,000 to 100,000 yen a month on Rakuten Ichiba, how much comes back through the Rakuten Mobile part of SPU (the Super Point Up Program)? I ran the numbers using only conditions I could confirm on the official pages, including the free periods for Saikyo U-NEXT and YouTube Premium. I also write out who it is not worth it for.
Rakuten Mobile Where Do You Contact Rakuten Mobile Support? The Channels Confirmed on the Official Page, and How to Proceed
Rakuten Mobile has several ways to get help: chat and phone, AI guidance, sign-up support, the community, my Rakuten Mobile and stores. Here are the channels confirmed on the official page and what isn't stated (as of October 8, 2026).
Telecom Technology A Week of Unauthorized Access Reports: What We Know About Rakuten Drive, G Point and IDCF Cloud, and What You Can Do Yourself
Unauthorized access reports kept coming from late September to October 7, 2026. We sort out what has been reported about Rakuten Drive, G Point and IDCF Cloud, what hasn't been written, and general steps you can take.
Rakuten Mobile ahamo Goes Up to 3,135 Yen for 40GB. What a Comparison with UQ, Y!mobile and Rakuten Mobile Shows
ahamo's price revision (3,135 yen for 40GB, new tiers) compared with UQ, Y!mobile and Rakuten Mobile, based on a Keitai Watch column. Facts and the author's view kept separate (as of Oct 7, 2026)
Telecom Technology Your Phone's Battery Drains Fast. Weak Signal and Settings May Be the Cause
Causes of fast battery drain, sorted into weak signal, connection settings, screen and apps, and battery wear. The order to check and the settings worth revisiting (general explanation)
Campaign Info This Week's Mobile Campaign Roundup (as of Oct 7): Conditions at 6 Carriers, and the Fine Print Behind the Headlines
Recent campaigns from Rakuten Mobile, SoftBank, au, LINEMO, Y!mobile and IIJmio, as far as reports and official pages confirm. Includes the conditions behind headlines like 1 yen a month and 47 yen for 2 years (as of Oct 7, 2026).
Rakuten Mobile Suddenly No Signal. A Network Outage? Where to Check on Rakuten Mobile and What to Do When It Won't Connect
When your phone worked yesterday but suddenly shows no signal, here is the order for checking whether it's an outage: isolating your own device, reading official notices, and what to do before contacting support
Rakuten Mobile Why Rakuten Mobile Prices Look Different Across Articles and Social Media: Tax-Included vs Tax-Excluded, and the Family Discount
Why Rakuten Mobile's price looks different from post to post. How the official Saikyo Family Discount prices, tax-included vs tax-excluded, and no-discount prices relate, as far as I could confirm (as of Oct 7, 2026)
Telecom Technology SMS Verification Code Not Arriving. Causes and Fixes to Try in Order
Causes when SMS codes for LINE or your bank don't arrive: signal, settings, SIM type, iPhone and Rakuten Link cautions, and how to resend, all in an order you can follow
Telecom Technology This Week's Mobile and Telecom News (Sep 30 - Oct 7): Rakuten Drive, au Roaming, ahamo, and a Flying Base Station
Five mobile and telecom stories from Sep 30 to Oct 7, 2026, as far as confirmed: the Rakuten Drive breach, the end of au roaming for Rakuten Mobile, ahamo's price hike, SoftBank's drone network, and campaigns.
Guide for Foreigners Free Wi-Fi Is Handy. But Don't Open Your Banking App on It
Free Wi-Fi at stations and cafes is handy, but safety varies by place. Here is what to watch for, and when it's fine or not to use it, as general guidance.
Rakuten Economy Unauthorized Access to Rakuten Drive. What the Reports Confirm, and What Users Should Check
Unauthorized access to Rakuten Drive announced on October 6, 2026. Stored data of 15,382 accounts was taken. The confirmed facts from reports, what hasn't been written yet, and what users should check
Campaign Info Rakuten Mobile Campaign Roundup (October 2026): The Conditions and Pitfalls of 10,000 Points for Switching and 9,000 for New Lines
Rakuten Mobile's first-time sign-up campaign (10,000 points for switching, 9,000 for new lines): conditions, pitfalls and other deals, as of Oct 6, 2026
Rakuten Economy Paying Your Phone Bill with Rakuten Points: Payment Methods That Don't Work, and Limits to Know
Rakuten Mobile lets you pay with saved Rakuten Points, but not with bank transfer, among other conditions. Here are the point payment terms and the SPU cap, as confirmed on the official page.
Rakuten Mobile How to Officially Request Better Rakuten Mobile Signal: When to Use the Signal Improvement Request Form
There is an official form to request better Rakuten Mobile signal at work or home. What to do first, what the form can and can't tell you, and home options, within what the official page states.
Telecom Technology 20 Years Without the Platinum Band: What SoftBank's Briefing Says About Spectrum Limits, and AI-RAN as the Next Move
At its 20th anniversary briefing, SoftBank described starting out without the platinum band and putting AI into base stations. Here is what was reported, with radio basics.
Telecom Technology Before Tethering Your PC: Three Pitfalls of Data, Battery, and Speed
Tethering turns your phone into a Wi-Fi router, but a PC uses more data than you'd expect. Here are the connection methods and three things to check before you start.
Telecom Technology Why Is "Unlimited" Data Still Slow? Speed Depends on Congestion, Not Data Volume
Even with unlimited data, speeds can drop in the evening or in crowds, because base station capacity is shared. Signal strength vs. congestion, and what to try, in general terms.
Telecom Technology Your Data Isn't Only Disappearing to Video: 5 Settings Worth Checking
Data vanishing without you noticing? Video isn't the only cause. App auto-updates and background data count too. How to check, and 5 settings to review.
Guide for Foreigners Lost Your Phone in Japan? What to Do First, and How It Affects SMS Verification
The first moves to make if your phone is lost or stolen in Japan, step by step. Suspending your line, finding your device, reporting to the police, and what happens when you can't receive SMS verification codes
Telecom Technology What's the Difference Between MNO and MVNO? Own the Road or Rent It. Which Is Rakuten Mobile?
Carriers are either an MNO with its own network or an MVNO renting it. Using a road analogy, we cover which one Rakuten Mobile is and how to choose.
Telecom Technology Weak Phone Signal? What to Try, in Order: Isolating Device, Settings, Location, and Network
A weak signal comes from your device, settings, location, or network. Try the easy fixes first, like airplane mode and a restart, to narrow down the cause.
Guide for Foreigners Before You Upgrade Your Phone: A Checklist So LINE and Banking Apps Don't Trip You Up
LINE, banking apps, and SMS verification are where phone upgrades go wrong. A checklist of what to do before you let go of your old phone.
Rakuten Mobile Calls That Aren't Free Even with Rakuten Link: 0570, 188, the Default Phone App, and SMS
Calls are free only from the Rakuten Link app. The default phone app costs 22 yen per 30 seconds. 0570 and 188 are excluded. SMS fees too (checked Oct 27, 2026)
Telecom Technology A Base Station in the Sky? SoftBank Beamed Mobile Signal From an Unmanned Aircraft at 3,000 m
SoftBank has successfully demonstrated service to handset on the ground from an unmanned aircraft 3,000 m up. We sum up how a temporary area can be built from the sky when disaster takes out base stations, limited to what was reported
Telecom Technology Connected to Wi-Fi but It's Slow? The Problem May Be Your Wi-Fi, Not Your Connection
When the Wi-Fi icon is showing but the internet is slow, the cause isn't always the connection itself. Here's how to narrow it down by comparing speeds with your mobile data, and what to check next
Guide for Foreigners Stuck Without a Japanese Phone Number: Why Foreign Residents Should Get a SIM Contract First
In Japan, LINE, banks, and many other services ask for a phone number and SMS verification. Here's why a data-only SIM isn't enough, and what to get first.
Telecom Technology Whether Your Phone Works on Rakuten's Network Comes Down to Frequency Bands. Here's How to Check
Whether you get a signal depends on the frequency bands your phone supports. Before using it on Rakuten Mobile, here's how to read band numbers and how to check.
Rakuten Mobile Rakuten Mobile's au roaming is ending. What changes? Facts and views, kept separate
The KDDI (au) roaming that Rakuten Mobile has relied on ends under the old framework at the end of September 2026. Here is what has been reported, what a columnist estimates and thinks, and how you can check for yourself.
Telecom Technology What Is a SIM Lock, Really? What to Check Before You Switch Carriers
A SIM lock ties a phone to one specific carrier. Phones released on or after October 2021 are generally unlocked, but older ones need checking. Here's how to check and how to unlock.
Guide for Foreigners Free domestic calls with Rakuten Link, free international calls with WhatsApp. The cheapest phone plan for foreign workers in Japan
Rakuten Mobile + Rakuten Link gives you unlimited free domestic calls. With unlimited data, WhatsApp and LINE calls to family back home cost nothing. All for ¥3,278/month
Guide for Foreigners How to Set Up Rakuten Mobile eSIM on Android (2026 Guide)
Step-by-step guide to activate Rakuten Mobile eSIM on Android phones. Works on Samsung, Pixel, and more.
Guide for Foreigners Rakuten Mobile for Foreigners in Japan: Sign Up Guide (2026)
Step-by-step guide to sign up for Rakuten Mobile with a residence card. Available in 8 languages.