FREQUENTLY ASKED QUESTIONS

We are here to help you get answers to your questions about OneSimCard phones and services.

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21. eSIM
    • Do you offer an eSIM option for iPhones, Androids or Tablets?

      Yes. The OneSimCard eSIM option is available for use with iOS and Android phones, smart watches and even Windows tablets.

      eSIM is not a physical SIM, but rather a program that can be downloaded to eSIM compatible phones and device.

      The list of supported devices includes:

      iOS:
      • iPhone 15 Pro Max
      • iPhone 15 Pro
      • iPhone 15 Plus
      • iPhone 15
      • iPhone 14 Pro Max
      • iPhone 14 Pro
      • iPhone 14 Plus
      • iPhone 14
      • iPhone 13 Pro Max
      • iPhone 13 Pro
      • iPhone 13 mini
      • iPhone 13
      • iPhone 12 Pro Max
      • iPhone 12 Pro
      • iPhone 12 mini
      • iPhone 12
      • iPhone 11 Pro Max
      • iPhone 11 Pro
      • iPhone 11
      • iPhone XS
      • iPhone XS Max
      • iPhone XR
      • iPhone SE 3 (2022)
      • iPhone SE 2 (2020)


      Apple iPad models with an eSIM:

      • iPad Pro 11" (1st Gen or later)
      • iPad Pro 12.9" (3rd Gen or later)
      • iPad Air (3rd Gen or later)
      • iPad (7th Gen or later)
      • iPad mini (5th Gen or later)

      Android:
      • Arrows A101 FC
      • Fairphone 4
      • Google Pixel Fold
      • Google Pixel 8 Pro
      • Google Pixel 8
      • Google Pixel 7a
      • Google Pixel 7 Pro
      • Google Pixel 7
      • Google Pixel 6 Pro
      • Google Pixel 6
      • Google Pixel 6a
      • Google Pixel 5
      • Google Pixel 4
      • Google Pixel 4a
      • Google Pixel 4 XL
      • Honor Magic 4 Pro
      • Honor Magic 5 Pro
      • Huawei P40
      • Huawei P40 Pro
      • Huawei Mate 40 Pro
      • Motorola RAZR 40 Ultra
      • Motorola EDGE 40 Pro
      • Motorola G53 5G
      • Motorola G52J 5G
      • Motorola G53J 5G
      • Nokia XR21
      • Nokia G60
      • Nokia X30
      • Nuu X5
      • Oppo Find X3
      • Oppo Find X3 Pro
      • Oppo Find X5
      • Oppo Find X5 Pro
      • Oppo Find N2 Flip
      • Oppo Reno 5 A
      • Oppo A55s
      • Oppo Reno6 Pro 5G
      • Rakuten Hand 5G
      • Rakuten Mini
      • Rakuten Big‑S
      • Rakuten Big
      • Samsung Galaxy A54 5G
      • Samsung Galaxy Fold
      • Samsung Galaxy Note20
      • Samsung Galaxy Note20 Ultra
      • Samsung Galaxy S23
      • Samsung Galaxy S23+
      • Samsung Galaxy S23 Ultra
      • Samsung Galaxy S22
      • Samsung Galaxy S22+
      • Samsung Galaxy S22 Ultra
      • Samsung Galaxy S21 5G
      • Samsung Galaxy S21+ 5G
      • Samsung Galaxy S21 Ultra 5G
      • Samsung Galaxy S20
      • Samsung Galaxy S20+
      • Samsung Galaxy S20 Ultra
      • Samsung Galaxy Z Flip
      • Samsung Galaxy Z Fold 2
      • Samsung Galaxy Z Fold 3 5G
      • Samsung Galaxy Z Fold 4
      • Samsung Galaxy Z Flip 3 5G Fold
      • Samsung Galaxy Z Flip 3 5G
      • Samsung Galaxy Z Flip 4
      • Samsung Galaxy Z Flip 5
      • Samsung Galaxy Z Fold 5
      • Sharp Aquos R8 Pro
      • Sharp Aquos Sense 7
      • Sharp Aquos Sense 4 lite
      • Sony Xperia 10 III Lite
      • Sony Xperia 1 IV
      • Sony Xperia 5 IV
      • Sony Xperia 10 IV
      • Sony Xperia 1 V
      • Sony Xperia 5 V
      • Sony Xperia 10 V
      • Xiaomi 12T Pro
      • Xiaomi 13
      • Xiaomi 13 Pro
      • Xiaomi 13 Lite

      Windows 10:
      Acer Swift 7, ASUS NovaGo, HP Envy x2, Lenovo IdeaPad Miix 630, Lenovo Yoga 630, Microsoft Surface Pro X/Go 2/Pro with LTE Advanced.

      Learn more about eSIM compatibility on the eSIM page.

       Note: iPhonesmanufactured for the Chinese Market have 2 physical SIM card slots and are not eSIM capable. Pixel 3a can't use eSIM if the phone was purchased in Japan, or if bought with Verizon or Charter service.
22. OneSim VoIP
    • Why can't I receive phone calls and SMS on my Android phone when the screen is off?

      Newer Android OS versions have settings that do not allow apps to run in the background by default. This means that you will get an SMS or a phone call only while your phone display is ON. Once the  phone goes to sleep, the app will get deactivated.

      To fix this, you need to make a change in your phone's battery optimization settings:

      Settings -> Apps and notifications -> See All Apps -> 1SimVoIP -> Advanced -> Battery -> Don't Optimize

      The settings path may slightly differ depending on the phone model, but usually it is located in the  App's Battery menu.
23. How To Use Questions
    • Can I forward calls from my OneSimCard phone to another number?

      Yes. Your Universal, Expedition and eSIM World OneSimCard mobile number can currently be forwarded to EU, Canada, USA, Russia, Ukraine and Belarus numbers. It's 100% free to forward your OneSimCard phone number to many countries including to U.S. or Canadian numbers. Forwarding to some countries, as well as to satellite phones, will carry a forwarding charge as listed in the Rates & Coverage page on OneSimCard.com.

      To enable/disable call forwarding from your online account:

      Log in at OneSimCard.com and go to the My SIM Cards menu. Select your SIM card number and enable/disable Call Forwarding on this screen.

      To enable/disable call forwarding from your phone:

      Dial *146*081*XXXXXXXXXXXXX# and press Send/Talk (where XXXXXXXXXXXXX is the forward-to number in international format: 00+countrycode+number)

      Newer SIM cards use *81* instead of *081*

      Example: to forward to U.S. number 1-617-555-1212, dial *146*081*0016175551212# and press Send/Talk.

      If you get an "Unknown Format?" message, dial *146*81*0016175551212#

      To disable call forwarding, dial *146*080# and press Send/Talk. If you get an "Unknown Format?" message dial *146*80# and press Send/Talk.

24. How To Use Questions
    • Do I need to change any settings on my phone when going abroad?

      Not Really. If you are planning to use Mobile Data, you will need to enable Data Roaming on your phone. Everything else in modern phones get done automatically. However, you should ensure that the APN on the device is correctly updated when the SIM card or eSIM card is enabled.
       
       
      Here is a video showing how easy it is to enable roaming:
      Here is a video showing how easy it is to check and add an APN:
      Android (APN demonstrated is for DataMax SIMs): https://youtu.be/j8fcJUpBj6k


      Universal, Expedition, & eSIM World SIM card types:

      Name: 1SIM

      APN: send.ee

      Leave all other settings alone

      DataMax, DataMax eSIM, & IoT Track SIM card types

                      Name: 1SIM (NOTE: Most IoT devices do NOT have a setting/field for “Name”)

                      APN : OSC (NOTE: The “O” is the LETTER O, NOT the number 0)

                      Leave all other settings alone

25. Rates and Cost Questions
    • Can I keep receiving calls made to my regular cell phone or landline numbers while traveling abroad?

      Yes, you can easily forward calls from your regular cell phone number, home phone, office, etc. to your OneSimCard phone while you're abroad!

      Your OneSimCard international Universal and Expedition SIM card comes with both a European and U.S. number. To forward your regular U.S. numbers to the SIM, just set them to forward to the U.S. number that's included with your SIM card. For eSIM World and DataMax eSIM, you can order Personal Extra Numbers (PENs) as needed for an additional cost.

      You can also order unlimited Personal Extra Numbers (PEN) - Local or Toll Free - in many different countries, including USA, Canada, UK, France, Italy and Spain. For example, if you work or live in the UK and want to keep receiving calls made to your regular UK numbers, just add a UK PEN to your SIM card and set up call forwarding to that new number.

      Calls received through a PEN will be charged an additional 20c/min to the incoming rate of the country you are in. The exception is calls received through a UK-Mobile PEN which is only charged an additional 25c per call.

      Please Note: Your subscription to a Personal Extra Number starts the moment your order is shipped. If you do not need your PEN to be active right away, you can always wait and order a PEN later at any time by logging in to your account.

      You can forward your calls to your 1SIM VoIP PEN. Simply forward all calls from your phone number to your 1SIM VoIP PEN using the directions below. Normal charges will apply for receiving calls to your 1SIM VoIP number (there will be NO extra $0.20, or $0.25 for UK PEN, cost to receive a call on OneSim VoIP).

      Different carriers use different ways of programming call forwarding. Below are instructions to setup call forwarding with various US wireless carriers. We urge you to test the call forwarding a few days prior to your trip, and to call your wireless carrier for assistance if needed.

      Alltel, , Verizon Wireless, Cricket Wireless

      To activate Call Forwarding:

      1. Press *72 on your cellular phone.
      2. Enter your ten-digit Second Personal OneSimCard phone number (area code + telephone number).
      3. Press OK/Send (a tone will confirm that Call Forwarding is active).

      * is a star character located on the keypad

      To deactivate Call Forwarding:

      1. Enter *720 on your cellular phone.
      2. Press OK/Send (a tone will confirm the deactivation).

      T-Mobile and AT&T Wireless GSM phones

      To activate Call Forwarding:

      1. Press *21* on your cellular phone.
      2. Enter your ten-digit Second Personal OneSimCard phone number (area code + telephone number) followed by the # key.

      To deactivate Call Forwarding:

      1. Enter #21# on your cellular phone.
      2. Press OK/Send.

       

26. Rates and Cost Questions
    • What is the cost to make calls from a OneSimCard phone to another OneSimCard phone?

      It depends on the country you're in when making the call. In many countries there is a special low rate of just $0.25/min to call another OneSimCard phone (only when dialing the other OneSimCard user's primary mobile number, not a Personal Extra Number). In other countries your cost will be our standard low outgoing call rate from that country.

      Example: two OneSimCard users are in Italy and one calls the other, the cost will be $0.25/min for the caller and free for the receiver.

      Visit our Rates & Coverage page and choose any country to view its current rates. Use the dropdown menus to see rates for calling to/from other countries.

      PLEASE NOTE: If you activate a discount call plan, the special rate to make OneSimCard-to-OneSimCard calls will not be available. You will be charged for those calls according to the discount call plan rate. 

      Another great benefit of using OneSim VoIP: To call using the 1SIM VoIP App to another user on the 1SIM VoIP App, this call is free, so long as you are calling the PEN associated with their 1SIM VoIP App.

       

27. OneSim VoIP
    • Which phone number will be shown on the caller ID when I make a call using OneSim VoIP?

      Your active OneSim VoIP Personal Extra Number (PEN) will be shown on the caller ID.
28. Troubleshooting Questions
    • Will a OneSimCard international SIM card work with my mobile phone?

      OneSimCard will work with almost any unlocked GSM tri-band or quad-band cell phone. A partial list of compatible cell phones that we have tested can be viewed here.

      If you need to unlock the phone, we suggest contacting your carrier or phone manufacturer for unlocking information or services.

      If your phone is not a quad-band phone, please make sure that the bands of your phone are those required in the country of your travel. You can look it up here.

      If you are still unsure whether your cell phone is compatible, contact support or purchase an international cell phone and SIM card bundle from us, which all come preloaded with our international SIM card, $10 balance  and OneSimCard Apps Installed.

29. Troubleshooting Questions
    • I have a Samsung phone. When I dial following your instructions it does not work. What's wrong?

      Some phones such as Samsung and some other brands require dialing a specific prefix 146 in front of the dialed string when used with a OneSimCard.

      For example, calling to USA: Dial *146*0016175551212# and press the TALK (or SEND) button
      * is a star character located on the keypad 
      • To check your balance dial  *146*099 and press the TALK (or SEND) button
      • To add funds dial *146*098XXXX*ZZ and press the TALK (or SEND) button,
        where XXXX - 4 last digit of your credit card on file, ZZ - Recharge amount
      • You need to press * on your phone in the above dialing sequences
      • Activation of voice mail *146*091 and press the TALK (or SEND) button
      • Deactivation of voice mail *146*090 and press the TALK (or SEND) button
      • Check number of messages in Voice Mail *146*094 and press the TALK (or SEND) button
      • To listen to voice mail *146*095 and press the TALK (or SEND) button

      The sequence *146* can be used from any phone. However, most phones do not require it.

      It is possible to make almost any phone entirely compatible, so you can call directly without using OneSimCard menu or *146* by following these simple programming instructions below.

      How to activate compatibility mode:

        1. Locate and Open "OneSimCard" Menu. ( It could  be displayed as STK Menu)

              2. Select "Settings"

        Newer SIM Cards: Select "Compatibility" and make sure "On" is selected
        Older SIM Cards: After selecting Settings:
        1. Agree with message by pressing "Yes"
        2. Dial digits "1101" and select "OK" (Screen will show "CC OptionX: ON" message)

          Bear in mind that if you have powered your telephone down, and have removed and reinstalled the battery, you will need to follow the programming steps outlined above, again.
          d when used with a OneSimCard.

      30. Troubleshooting Questions
        • I have an Apple iPhone. When I dial following your instructions it does not work. What's wrong?

          This reply does not apply to OneSimCard Europe & More SIM or newer SIM cards purchased after January 2017.
          Older SIM cards might require entering the compatibility code on your  iPhone.

          How to activate compatibility mode:

           1. Locate OneSimCard Menu.

           On iPhones it is called SIM Applications menu and is located under Settings- Phone menu

          1. Open "OneSimCard" menu ( SIM Applications)
          2. Select "Settings
          Newer SIM Cards: Select Compatibility option and make sure "On" is selected
          Older SIM Cards: After selecting Settings:
          1. Agree with message by pressing "Yes"
          2. Dial digits "1101" and select "OK" (Screen will show "CC OptionX: ON" message)

          Bear in mind that if you have powered your telephone down, and have removed and reinstalled the battery, you will need to follow the programming steps outlined above, again.


          We strongly recommend you to watch very short video tutorials for iPhone that will help you to understand how to make calls, SMS and data on your OneSimCard iPhone.
          If your phone is not Jail-Broken, you still can use OneSimCard Assist app available from iTunes. This app will help you to dial numbers properly by correcting mis-dialed numbers and will allow easy access to OneSimCard functions like checking balance, recharging your SIM, activating discounts and others.

          These videos are available in the Help Menu of your OneSimCard Portal. You need to log in to your OneSimCard account first and then proceed to the Help Menu to be able to access these videos.

          Again, this is for older SIM Cards. Newer SIM cards do not require entering any codes in iPhone or other types of phones.

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