We are here to help you get answers to your questions about OneSimCard phones and services.
Which phone number will be shown on the caller ID when I make a call using OneSim VoIP?
Your active OneSim VoIP Personal Extra Number (PEN) will be shown on the caller ID.What is the cost to make calls from a OneSimCard phone to another OneSimCard phone?
It depends on the country you're in when making the call. In many countries there is a special low rate of just $0.25/min to call another OneSimCard phone (only when dialing the other OneSimCard user's primary mobile number, not a Personal Extra Number). In other countries your cost will be our standard low outgoing call rate from that country.
Example: two OneSimCard users are in Italy and one calls the other, the cost will be $0.25/min for the caller and free for the receiver.
Visit our Rates & Coverage page and choose any country to view its current rates. Use the dropdown menus to see rates for calling to/from other countries.
PLEASE NOTE: If you activate a discount call plan, the special rate to make OneSimCard-to-OneSimCard calls will not be available. You will be charged for those calls according to the discount call plan rate.Â
Another great benefit of using OneSim VoIP: To call using the 1SIM VoIP App to another user on the 1SIM VoIP App, this call is free, so long as you are calling the PEN associated with their 1SIM VoIP App.
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I have a OneSimCard SIM and my phone will not register on a roaming network, what's wrong?
Sometimes when moving from the USA, Canada or Mexico to another country, the SIM card will need to be reset to properly register on a new country roaming network.
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. Â
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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.Â
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.
What is an eSIM & how does it work?
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.
Can I use Facetime, WhatsApp, Telegram, Discord, iMessage, and other messaging Apps with eSIM?
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.
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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