FREQUENTLY ASKED QUESTIONS

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11. Rates and Cost Questions

    • Is it free for someone to call my OneSimCard number using Viber?

      Through a unique partnership with Viber, your primary OneSimCard number (+372) can be called free of charge for any Viber user! (requires activation and special dialing instructions, see below)

      HOW: When this feature is activated, Viber users can call OneSimCard numbers for free by using a special dialing format +372800XXXXXXXX, where XXXXXXXX is the rest of the OneSimCard phone number after 372. For example, a OneSimCard user with the phone number +37212345678 should be called by dialing +37280012345678.

      TO ACTIVATE: Log in to your OneSimCard account and go to the My SIM Cards menu. Scroll down to where it says "Incoming Viber Calls" and click Enable to activate this option.

      COST: The call is free for the Viber user. The cost of receiving the Viber call is the same as receiving a call through a Personal Extra Number (PEN), i.e. the regular incoming call rate in the country you are in plus 20c/min. In countries with free incoming calls, like Italy or Japan, the cost will be just 20c/min.

      PLEASE NOTE:

      • When dialing in Viber, if Viber user chooses the Estonian country code in the menu then they should just dial 800XXXXXXXX because the +372 is added automatically.
      • If the “free calls to OneSimCard from Viber” option is not activated for a particular OneSimCard number, when a Viber user dials +372800XXXXXXXX they will hear an automatic message: “The mobile phone is either switched off or out of coverage area.”

      PLEASE NOTE: Viber is not available for the DataMax or DataMax eSIM
12. 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
13. 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.
14. 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.
15. Troubleshooting Questions

    • I just arrived in a foreign country and my phone is not working, what should I do?

      If you left your phone on during your flight or cruise then you should fully power down and restart your phone. Once your phone powers back on it should automatically select an available roaming network.

      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.
      In some countries like in USA turning off 3G mode of the phone will make it quicker for the phone to register on the network.
16. Ordering Questions

    • Will my order require a signature upon delivery?

      Yes, please assume that your order will require a signature if it contains a cell phone.
17. Ordering Questions

    • Can I upgrade my Standard SIM to a Universal, DataMax or DataMax eSIM SIM or my regular size SIM to a micro or nano SIM?

      Yes. If you would like to upgrade your Standard, Plus, Europe & More, Expedition version SIM card to a Universal, DataMax, or DataMax eSIM SIM card, or upgrade a regular size SIM card to a micro-SIM card (for example, to use in an iPhones) then place your order online by selecting the product option on our Mobile Accessories page here. In the shopping cart you will be able to select your upgrade.

       
18. 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
19. OneSim VoIP

    • How do I know if the Personal Extra Number (PEN) I currently have is OneSim VoIP compatible?

      Log in to your OneSimCard account, go to the My Sim Cards menu and scroll down. If your PEN is VoIP compatible you will see an option to create a OneSim VoIP account. At this time all OneSimCard PENs are SIM VOIP capable except for UK Mobile numbers.
20. OneSim VoIP

    • What is the cost of calling between two OneSim VoIP phones?

      Calls between two OneSim VoIP phones are absolutely free.

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