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
    • 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.

22. OneSim VoIP
    • When making an outgoing call how do I select which way the call should go: through regular roaming or through OneSim VoIP?

      To make an outgoing call using OneSim VoIP, you need to be registered on a Wi-Fi network and have the OneSim VoIP app running on your phone. You should make the call using the OneSim VoIP app dial pad. To make a call the regular roaming way,you should make a call from your regular phone dial pad. 

      NOTE: Regular roaming calling is NOT available on DataMax or DataMax eSIM cards. To use voice you will need to use the OneSim VoIP app

23. OneSim VoIP
    • Does voicemail work with OneSim VoIP?

      Yes. If you are not available to answer the OneSim VoIP call or if the OneSim VoIP app is turned off, the call will be routed through our standard roaming network. If the call is not answered it will be sent to your OneSimCard voicemail box. 

      NOTE: Voicemail is not available for DataMax or DataMax eSIM cards with OneSim VoIP.

24. 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.
25. 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 and data use optimization settings:

      Settings -> Apps and notifications -> See All Apps -> 1SimVoIP -> Advanced -> Battery -> set to "Unrestricted"


      Settings -> Apps and notifications -> See All Apps -> 1SimVoIP - turn Background Data and Unrestricted Data Usage both ON.

      Restart the phone.
26. 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.


       

       

27. How To Use Questions
    • How do I prevent the service from expiring?

      The OneSimCard phone number has no expiration, provided you made at least 1 call or sent an SMS once every 12 months.

      However, the funds on the SIM expire 10 months after your last recharge. The minimum recharge amount is $25. You can keep the balance from expiring by simply recharging at least once every 10 months. If you let your balance expire, then all you need to do to get the service up and running again is to log in and add funds to your SIM card. Automatic recharge will be canceled if you let your funds expire.

      NOTE: For Physical 3-in-1 DataMax & DataMax eSIM SIM cards, if the SIM card has no balance, the SIM will expire and be removed from the account after 7 days, unless there is a data package currently active on the SIM (not a future activation). If there is no balance on the SIM and the active data package expires, the SIM will expire 7 days following the expiration of the active data package.

       

      An expired SIM can be restored for a $10.00 restoration fee plus a recharge of at least $25.00.

       

28. 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.

29. Ordering Questions
    • Can I transfer my phone numbers and balance from my standard OneSimCard SIM when I upgrade to a OneSimCard Plus SIM or other SIM card?

      • We can move your airtime balance and PEN if any from your standard SIM to the Universal, Expedition, eSIM World, DataMax, or DataMax eSIM SIM if you upgrade the SIM or your sim is lost or damaged and you are buying a replacement SIM. The replaced SIM will be permanently deleted from your account.. 
      • We can move your Personal Extra Number from your sim to any other SIM. There is $5 charge for this.
      • We cannot transfer your primary +372 number from your Standard SIM to any other SIM, you will get a new number when you upgrade. 
      • NOTE: DataMax and DataMax eSIMs do not come with any primary phone number. You can purchase a PEN to use voice and SMS with our OneSIM VoIP App
30. Rates and Cost Questions
    • What is time validity of OneSimCard SIM?

      All SIM types are valid for 1 year after the last billable use - phone call, sent SMS or data use.

      The SIM balance for all types of OneSimCard SIMs is valid for 10 months after the last recharge. Each recharge extends the balance for the next 10 months period. If you do not recharge within the 10-month period, any remaining balance will be forfeited.

       

      NOTE: For Physical 3-in-1 DataMax & DataMax eSIM SIM cards, if the SIM card has no balance, the SIM will expire and be removed from the account after 7 days, unless there is a data package currently active on the SIM (not a future activation). If there is no balance on the SIM and the active data package expires, the SIM will expire 7 days following the expiration of the active data package. Additionally, if a data package is purchased, and set for future activation, the inactive data package will expire after 6 months from the date of purchase.

       

      An expired SIM can be restored for a $10.00 restoration fee plus a recharge of at least $25.00.

       

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