FREQUENTLY ASKED QUESTIONS

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

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31. 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.
32. 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.

       

33. Troubleshooting Questions
    • I have a OneSimCard SIM and my phone will not register on a roaming network, what's wrong?

      Sometimes when moving from the USA, Canada or Mexico to another country, the SIM card will need to be reset to properly register on a new country roaming network.

      • If you have the OneSimCard Menu on your phone (it may be called Sim Application Menu on iPhones or SIM Toolkit on Androids), go to the menu, scroll down to Settings and enter Service Code 2003 and confirm, then Code 000 and confirm. For older SIM cards after this enter Service Code 1101 and confirm. Turn the phone off and then back on. 

      • If you do not have access to the OneSimCard Menu then turn off your phone, remove the battery for 20 seconds, reinstall the battery and then turn back on your phone.
34. 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.
35. OneSim VoIP
    • Is text messaging available on the OneSim VoIP App?

      OneSimCard SIM VoIP users with US and Canadian numbers may now send and receive text messages over the OneSim VoIP app on iPhone and Android. The cost to sending a message is $0.05 per text to most countries. Receiving message is $0.05.  

       

      OneSimCard SIM VoIP users with US and Canadian numbers may now send and receive text messages over the OneSim VoIP app on iPhone. The cost to send or receive each message is $0.05. 

36. eSIM
    • How do I install my eSIM?

      Before purchasing, please ensure you have verified that your device is unlocked and one of the supported devices. Installation is completed by using your phone to scan the QR code of the purchased eSIM.  You may scan the QR code by displaying it on the computer screen, another device, or a printed copy. You can also "scan" the QR code without needing a second device using the QR code we emailed to you. You can see instructions for this here:

      Install eSIM without a second device for iPhone instructions

      Install eSIM without a second device for Android instructions

      If you’ve already purchased OneSimCard eSIM, you can see full installation instructions and access your QR code from the Recharge menu in your online account. Make sure eSIM is selected in the Select SIM Card drop down menu.

      If you have not purchased your eSIM yet, learn more about international eSIM here.

37. eSIM
    • What is an eSIM & how does it work?

      eSIM is not a physical SIM. It is a piece of software downloaded to a compatible phone. So there is no shipping involved with delivering eSIM.


      eSIM makes your iPhone or Android phone to be a dual SIM phone. This means that you can use two sim cards on the phone at the same time. You can select which SIM card is used for calls and texts, and which one is used for data. You can select which sim card is to be the primary and which one not to be used. You can make these changes from the settings of your phone at any time. In short - eSIM offers greater flexibility to your eSIM compatible phone. It allows you to use the service provider of your choice - whether you are traveling or staying home.


      OneSimCard eSIM can be installed only on a single device. It can't be moved to another device, but it can be re-installed on the original device up to 3 times if required.
38. eSIM
    • Do I need to have Data Roaming turned on for eSIM to work?

      Yes. Data Roaming should be enabled on your phone for eSIM for data to work. Calls and texts on eSIM World should work with or without it.

39. eSIM
    • Can I use Facetime, WhatsApp, Telegram, Discord, iMessage, and other messaging Apps with eSIM?

      Yes, you can use your messaging apps with eSIM World, which now offers a mobile number ID. 

      For DataMax eSIM, you can use these Apps as you already do. Please ensure your messaging account is already setup with your primary carrier’s phone number because you cannot sign up for these services with the DataMax eSIM number.

      Additionally, the eSIM data service can be used for the actual data part of your communications. So, when you are installing eSIM on phone, you can select the Primary service for Facetime and iMessage and then if your selected eSIM to be your primary data service, the communications will go over eSIM mobile data.

40. Troubleshooting Questions
    • When I dial following your instructions it does not work. What's wrong?

      This answer applies to SIM cards purchased before January 1, 2017.

      Some phones, such as Samsung, some Motorola, Android and Apple iPhones, require special dialing instructions or simple OneSimCard settings menu changes in order to make calls.

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

      How to activate compatibility mode:

        1. Locate OneSimCard Menu.

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

               On Androids it is called SIM Toolkit app or OneSimCard app and it looks like one of the apps.

         

      1. Open "OneSimCard" menu ( SIM Applications, SIM Toolkit, STK)
      2. Select "Settings
        Newer SIM Cards: Select Service Code option and follow instructions below:
        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.

          If for any reason after entering compatibility code, you still do not get a ringback or you get the ringback the first time you make a call, but second time it would not work, please enter code 802 into the Service Code window instead of 1101 as provided above.

           

          iPhone users can download OneSimCard Assist App from iTunes that will takes care of the iphones compatibility issues, except for removing the ringback.


          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* and # at the end can be used from any phone. However, most phones do not require it.

          We strongly recommend you to watch very short video tutorials that will help you to understand how to make calls, SMS and data on your OneSimCard Phone.


          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 troubleshooting advice might be needed only for older SIM cards.

           

           

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