As the latest iPhone models are expensive, many people are considering purchasing a used one.

Even with used iPhones, there are cases where products in like-new condition are sold, allowing you to acquire an almost-new iPhone at a lower price than usual.

 

This article introduces how to use a used iPhone for each carrier.

We've also summarized the key points to check and set up after purchasing a used item, so please refer to this if you are considering buying a used iPhone.

 

 

How to Use a Used iPhone

 

A used iPhone can be used by simply replacing the SIM card.

 

However, if there is a SIM lock or activation lock, it needs to be unlocked, so caution is required.

After purchasing a used iPhone, insert the SIM card into the device.

 

Insert a SIM ejector tool into the small hole on the side of the device, remove the tray, set the SIM card in the correct orientation, and then insert it.

Once the SIM is correctly set, charge the device.

 

If the charge is insufficient, the power may turn off during use, so wait until it is fully charged.

Turn on the power, select Japanese as the language, and then proceed with the initial setup.

 

An Apple ID is required to use an iPhone, so please have your ID and password ready.

 

Logging in with your Apple ID allows you to restore data such as contacts and calendars.

You will also be able to use various related services that are associated with your Apple ID.

For security settings, set a passcode, screen lock, and fingerprint/face authentication.

 

Next, download apps via Wi-Fi or LTE connection.

 

Official apps are available for each carrier, such as Docomo, au, SoftBank, and Rakuten Mobile.

Many used items have not had software updates, so update to the latest software.

 

 

How to Use a Used iPhone with Different Carriers

 

 

While iPhone specifications differ by generation, usability also varies by carrier.

Here's how to use and what to be aware of for the three major carriers and Rakuten Mobile, totaling four companies.

 

 

Docomo

 

Prepare your SIM card.

If you are already subscribed to Docomo, you can use your existing SIM card.

 

Insert the SIM card into the iPhone's SIM tray, and after booting up, perform various settings and connect to Wi-Fi.

For iPhones with iOS 16 or later, APN settings are automatically configured when a SIM card is inserted or an eSIM is used.

After setting the APN, connect to Wi-Fi, reset all settings, and restart the device.

 

【Note】 Docomo supports iPhones from the iPhone SE (1st generation) for both irumo and ahamo, but does not verify or guarantee the operation of some mobile phone models.

 

It is recommended to inquire with the purchase source regarding supported communication methods and SIM unlock status. (*)

 

If you use a Docomo SIM or have a Docomo d ACCOUNT, you can install the My docomo app, log in, and connect to services.

 

*Reference: NTTdocomo "Precautions when using a mobile phone you have prepared with a Docomo SIM card" 

 

 

au

 

Prepare your SIM card.

If you are already subscribed to au, you can use your existing SIM card.

 

Insert the SIM card into the iPhone's SIM tray, and after booting up, perform various settings and connect to Wi-Fi.

For iPhones with iOS 16 or later, APN settings are automatically configured when a SIM card is inserted or an eSIM is used.

After setting the APN, connect to Wi-Fi, reset all settings, and restart the device.

 

【Note】 au provides a "List of Verified Devices" where you can search for compatible devices.

It supports iPhone 6s and later models, but is limited to domestic models and does not include overseas models. (*)

During initial setup, enter your au ID and au PAY settings. Enter your ID and password, and install and set up the au PAY app, etc.

 

*Reference: au "List of Verified Devices" 

 

 

SoftBank

 

Prepare a new SIM card.

If you are already subscribed to SoftBank, you can use your existing SIM card.

 

Insert the SIM card into the iPhone's SIM tray, and after booting up, perform various settings and connect to Wi-Fi.

For iPhones with iOS 16 or later, APN settings are automatically configured when a SIM card is inserted or an eSIM is used.

After setting the APN, connect to Wi-Fi, reset all settings, and restart the device.

 

【Note】 You can check which iPhones can be used with SoftBank from the "USIM Verified Device List".

As of October 2024, models from iPhone 8 onwards are supported.

For details, please check the official website's "USIM Verified Device List." (*)

During initial setup, download the My SoftBank app and log in with your My SoftBank ID and password.

 

*Reference: SoftBank "USIM Verified Device List" 

 

 

Rakuten Mobile

 

Prepare your SIM card.

If you are already subscribed to Rakuten Mobile, you can use your existing SIM card.

 

Insert the SIM card into the iPhone's SIM tray, and after booting up, perform various settings and connect to Wi-Fi.

For iPhones with iOS 16 or later, APN settings are automatically configured when a SIM card is inserted or an eSIM is used.

After setting the APN, connect to Wi-Fi, reset all settings, and restart the device.

 

【Note】 With Rakuten Mobile, compatibility varies depending on where the iPhone was purchased.

Docomo iPhones are compatible from the iPhone SE (1st generation) onwards.

Y!mobile iPhones are only compatible with 6s, 7, 11, SE (2nd generation), 12, and 12 mini.

 

Rakuten Mobile supports 5G, but there are differences in communication speed, quality, and service area compared to the three major carriers.

 

 

*Reference: Rakuten Mobile "Check Device Compatibility" 

 

What to Do After Buying a Used iPhone

 

 

Here's what to do after purchasing a used iPhone:

 

【Checkpoints after purchasing a used iPhone】

• Operation check
• Data transfer
• ID/password settings
• "Find My iPhone" settings
• Email settings
• iCloud settings
• App installation

 

Perform operation checks, data transfer, ID/password settings, and install necessary apps.

 

 

 

Operation Check

 

An operation check confirms whether the device works correctly and if apps can be used.

 

Turn on the power and ensure the screen displays clearly and buttons function properly when pressed.

Voice (call) functions and app behavior also need to be checked.

 

If, by any chance, the screen colors are odd, it's not bright enough (insufficient brightness), authentication fails, or there's touch ghosting, it suggests a device malfunction.

Consult the seller, a repair shop, or Apple Support.

 

Before checking the device's operation, you might find that parts are missing, or there are signs of water damage or breakage on the used device.

If there's any issue with the device itself, consider repairing or replacing the unit.

 

 

Data Transfer

 

Data migration is the process of transferring data from an old device to a new one.

If you're switching from Android to iPhone, you'll need to transfer data such as contacts stored on your Android device.

 

For iPhone to iPhone transfers, you can use the "Quick Start" feature.

When you bring the devices close together, the Quick Start feature activates, and data is automatically synced by following the prompts and entering your ID.

 

A point to note is that Quick Start cannot be used if the destination iPhone has already completed its initial setup.

After completing the operation check, perform Quick Start first without proceeding with the initial setup.

 

For Android to iPhone transfers, you can also use the "Quick Start" feature, but by downloading the "Move to iOS" app from Google Play, you can smoothly switch from an Android device to an iPhone or iPad.

*Data can also be migrated from Huawei's HarmonyOS via the "Move to iOS" app on Google Play.

 

 

 

ID and Password Settings

 

On an iPhone, you will either create an Apple ID or log in with an existing one.

Android users, for example, should create a new Apple ID and set it up.

 

To create a new Apple ID, go to "Settings," then "Sign in to your iPhone," "Don't have an Apple ID or forgot it?", and then "Create a Free Apple ID."

Enter your name, date of birth, and email address to proceed. If you don't have an email address, get a free iCloud email address.

 

Follow the on-screen instructions to verify your email address, then set a password.

You can specify your country/region and set up two-factor authentication, or skip this step.

After verifying your email address, sign in to your newly acquired Apple ID.

You may also be asked to enter a phone number and payment method.

 

 

"Find My iPhone" Settings

 

Next, set up "Find My iPhone" in case of loss.

 

From "Settings," tap your name, open "Find My," and turn on "Find My iPhone."

You can also turn on "Find My network" to locate your device even when it's offline.

To find your device using a map, turn on "Send Last Location" at the bottom of the screen.

 

 

Email Settings

 

This is the process for setting up your email, such as Gmail or provider email.

Go to "Settings," then "Apps," "Mail," and tap "Accounts," then "Add Account."

 

Select a service (e.g., iCloud or Microsoft Exchange) and enter the respective account information.

Next, tap "Other," then "Add Mail Account," and enter your ID, server information, and so on.

 

 

iCloud Settings

 

Once you have an Apple ID, you can set up iCloud.

Select the items you want to back up to storage and turn them ON.

 

 

App Installation

 

Finally, install the necessary apps.

By signing in with your Apple ID, you can select the apps you are using from the App Store.

 

 

Understand How to Use and Set Up a Used iPhone

 

 

This article introduced how to use a used iPhone, including important points by carrier and setup methods.

 

Used items carry the risk of device malfunctions and failures, but the condition varies from device to device.

Performing an operation check allows you to detect issues early.

 

Since battery capacity and usage restrictions differ for each device, detailed checks are required during the initial setup phase.

iPhones can be used by swapping out the SIM, but there are points to be aware of for each carrier.

 

Please start using your device after understanding the precautions and setup methods.

 

The official online store for used smartphones and tablets, "PRODIG", sells used iPhones.

 

Although we conduct thorough inspections, if any trouble occurs within 180 days of product arrival, we promptly handle returns and exchanges, so please consider us.

 

Click here for a list of used iPhone products offered by PRODIG

 

Click here for a list of used smartphone products offered by PRODIG