We are here to help you get answers to your questions about OneSimCard phones and services.
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.
The  eSIM World, eSIM Asiania, OneSimCard Europe & More and Universal SIM cards do not use the callback to make an outgoing call in over 70 countries.
Currently, the mobile application to remove the callback on other SIM cards is not available.
How do I make a call using OneSimCard global cell phone service?
To make a call:
With Europe & More, Univesal and eSIM World that do not use the callback to make a call, you will just get connected.
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With OneSimCard Plus SIM or Expedition (formerly Data & Roam) SIMs:
After pressing the TALK/SEND button you will see a variable message on the screen (for example 'Wait for call') which you can ignore and your phone will ring back in a few seconds. Answer this ring as you normally would answer any incoming call. Your call will then be connected.
If you are unsure about how to properly dial an international number, follow this link for detailed country by country dialing instructions.
For Physical 3-in-1Â DataMax, and DataMax eSIM cards, you can place calls using our low cost OneSIM VoIP service. OneSim VoIP costs much less than traditional voice roaming.
I am traveling in Saudi Arabia and can receive calls, but I can't make an outgoing call. What should I do?
Local carriers in Saudi Arabia sometimes block standard OneSimCard outgoing calls. If this happens you need to either (a) enter a compatibility code into the settings of your phone or (b) initiate your call by sending an SMS message from the regular SMS menu (not the OneSimCard menu) of your phone.
How To Activate Compatibility Mode:
Bear in mind that if you have powered your telephone down and removed and reinstalled the battery, you will need to follow the programming steps outlined above again.
How To Deactivate Compatibility Mode:
How To Dial Without Activating Compatibility Mode:
Initiate your call by sending an SMS message from the regular SMS menu (not the OneSimCard menu) of your phone.
For example, to call from Saudi Arabia to Boston USA you should go to the SMS menu of the phone and send a message:
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There are no special instructions to receive calls in these countries.
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