FREQUENTLY ASKED QUESTIONS

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

Back to Main Support Page

41. OneSim VoIP
    • How does OneSim VoIP work when the call is received?

      When someone dials your OneSim VoIP enabled Personal Extra Number (PEN), the system will first check if your OneSimCard phone is registered with the OneSim VoIP app on a Wi-Fi network. If it is registered, the call will be sent using VoIP. If the OneSim VoIP app is not running or it is not registered on a Wi-Fi network, then the call will be sent using the standard OneSimCard roaming network and charged our standard roaming rates.
42. OneSim VoIP
    • I can make calls through OneSim VoIP. However incoming calls are going through my roaming SIM. What's wrong?

      If your incoming calls are not being routed through the OneSim VoIP app then you are either not connected to Wi-Fi or the OneSim VoIP app is not active.

      Please make sure to check your phone's sleep settings, as they are usually preset to have Wi-Fi turn off when the phone enters sleep mode. To prevent this and to keep OneSim VoIP active for incoming calls, find the settings in your phone and set it so Wi-Fi does not turn off when the phone enters sleep mode.

      Note: if the OneSim VoIP logo on the top of your phone display is gray then you will not be able to receive calls through the application. When the logo is yellow that means you are connected and can receive calls through OneSim VoIP.
43. 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. 

44. 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.

45. 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.

46. 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.
47. 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.

48. Troubleshooting Questions
    • I just activated my SIM card and can't make a successful test call. What's wrong?

      If you just activated your SIM card and can not make a test call by following the instructions in the user manual, you will likely just need to power off the phone and power it back on again. The phone should automatically re-register with one of our partner networks. Remember, if you answer the test call when it rings you will be charged for the call.
      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.

49. Rates and Cost Questions
    • How much does it cost to receive a call with OneSimCard?

      For Universal, Expedition, and eSIM World SIM cards, receiving calls is free in over 150 countries when received on your primary European phone number, including in most of Europe. To receive a call on your U.S. number or other Personal Extra Number, there is an additional per minute rate added. View all international cell phone rates.

      If you receive a call through a Common Access Number or Personal Extra Number (such as a U.S. number) there is an additional charge of 20c/min. In countries with free incoming calls this would be your only charge per call.

      For DataMax and DataMax eSIM card types, you can make and complete calls for a fraction of the cost of traditional cellular roaming (including on tablets) using the 1SIM VoIP App available on Google’s Play Store and Apple’s App Store:

       

      Google Play: https://play.google.com/store/apps/details?id=org.onesimvoip&hl=en_US&pcampaignid=pcampaignidMKT-Other-global-all-co-prtnr-py-PartBadge-Mar2515-1

       

      Apple App Store: http://itunes.apple.com/us/app/onesim-voip/id510371587

       

      For Universal, Expedition, and eSIM World SIM cards,  all incoming SMS text messages are free to receive when received on your primary European number. Add 9 cent per SMS when receiving text on US or Canada PEN.

      For DataMax and DataMax eSIM SMS messages are sent and received using the 1SIM VoIP App. The cost to receive SMS using the 1SIM VoIP App is $0.05 in most countries, The cost to send an SMS using 1SIM Voip App is $0.10 in most countries. See all rates on our international cell phone rates page.


       

       

50. How To Use Questions
    • What Is the Difference Between "Direct Dial" and "Callback Dial" calling?

      Direct Dial calling allows the caller to enter the international  call prefix, country calling code and telephone number and then be directly connected to the person they are calling. This is how you dial when using your regular mobile service. Direct Dial Calling is standard on the OneSimCard Europe & More, OneSimCard Universal and eSIM.

      Callback calling also allows the caller to enter the international  call prefix, country calling code and telephone number. After the called number is entered, the user immediately receives an incoming call connecting the user to person called. Callback is very simple to use and allows for low cost calling on the OneSimCard Plus and OneSimCard Expedition (formerly Data & Roam). Callback does not increase the connection time. It is the same as with Direct Dial.

<<   1   2   3   4   5   6   7   8   >>  

© 2006-2026 Belmont Telecom Inc., DBA OneSimCard.com. All rights reserved