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.
I have a Samsung phone. When I dial following your instructions it does not work. What's wrong?
How to activate compatibility mode:
 1. Locate and Open "OneSimCard" Menu. ( It could  be displayed as STK Menu)
    2. Select "Settings"
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.
d when used with a OneSimCard.
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.
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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.
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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:Â Dial *146*0016175551212# 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.
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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 can I dial '+' on my phone when making call?
Note: You can always dial 00 instead of + when making outgoing calls. For example, to reach OneSimCard customer service in the USA you can just dial 001 617 3138888.
You should consult the phone manual for this info. Different manufacturers have specific ways to access the '+' key, so make sure you know yours.
Here are few known ways:
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I have an Apple iPhone. When I dial following your instructions it does not work. What's wrong?
 1. Locate OneSimCard Menu.
 On iPhones it is called SIM Applications menu and is located under Settings- Phone menu
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.
When I try to make a call, I get a message 'Call is modified and cannot be made'. What does that mean?
Some phone models do not allow direct dialing with older OneSimCard SIMs sold before January 1, 2017.
To get around this problem, you should try either of these methods:
* is a star character located on the keypad
Other examples of how to use the *146* dialing prefix if necessary:
The prefix *146* and # at the end can be used from any phone. However, newer OneSimCard SIM do not require it and you should be able to dial codes directly, 091, 094, 095, 099 or 098XXXX*XX Talk.
If you have an older SIM and the dialing does not work without entering *146*, please follow these simple instructions to remove the need to dial *146*:
How to activate compatibility mode:
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 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 and it looks like one of the apps
Newer SIM Cards: Select Compatibility option and make sure "On" is selected
Older SIM Cards: After selecting Settings:
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.
When dialed directly, some Nokia and other phones can display message: "Call is not allowed" or "Call is barred". Just ignore this message and wait for the ring-back for 10 seconds or so.
Is there a 911 emergency number in Europe that can be used with OneSimCard service?
Yes, in Europe the emergency number is 112. You can use 112 in Europe to report real emergencies to local authorities in the country of stay. The 3 digit number should be dialed directly without any additional digits in front of the number.
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For DataMax and DataMax eSIM SIM cards, while there is no voice calling feature without the use of 1SIM VoIP, which doesn’t support emergency calling, most cell phones ALWAYS allow you to call emergency numbers, even without a SIM inserted into the phone. In Europe the emergency number is 112. You can use 112 in Europe to report real emergencies to local authorities in the country of stay. The 3 digit number should be dialed directly using the regular phone app (NOT the OneSim VoIP App) without any additional digits in front of the number.
I have an iPhone and am receiving charges for SMS sent to a UK mobile number 447786205094. Why?
This is a known issue with Apple's Facetime and iMessage applications on Apple iPhone devices. We recommend disabling Facetime and iMessage so it will not be able to automatically send SMS to this 447786205094 number. Any SMS sent to this number automatically by your phone can not be refunded by OneSimCard. Additional questions regarding iPhone applications and how they communicate should be directed to Apple Support.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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