We are here to help you get answers to your questions about OneSimCard phones and services.
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.Â
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
What are the advantages of using OneSim VoIP?
The main advantages are significant cost savings and the ability to call from countries where there is no voice roaming coverage available, or for DataMax or DataMax eSIMs
OneSim VoiP can be used from any Android or Apple ( iOS) device to make international LD calls even when you are not traveling. OneSim VoIP does not require having OneSimCard SIM being installed in the phone. OneSim VoIP can be used with Wi-Fi or 3G/4G - no difference. You just need to have OneSimCard account with the SIM VoIP capable PEN. Calling using OneSim VoIP will cost most of the time less than any other way of calling.
OneSim VoIP is available with the following SIM cards: Plus, Expedition (formerly Data & Roam),  Europe & More, DataMax, and DataMax eSIM.How do I enable roaming on my Android Phone?
This is very simple!ÂDoes iPhone Hotspot work with OneSimCard?
Yes. All unlocked iPhones' Hotspot feature works with OneSimCard SIM.What is the cost of calling between two OneSim VoIP phones?
Calls between two OneSim VoIP phones are absolutely free.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.Â
NOTE: Voicemail is not available for DataMax or DataMax eSIM cards with OneSim VoIP.
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.
How does eSIM works?
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.
What should I do if my OneSimCard phone or SIM card is lost or stolen?
If your phone or SIM card is lost or stolen and automatic recharge is on, this could be a serious problem.
To prevent this, log in to your account and activate the option to block your service immediately after you notice your phone or SIM card is missing. You can find this option in the My SIM Cards menu. Your OneSimCard service for this SIM card number will be instantly blocked. The remaining balance on your lost SIM can be transferred to another SIM card on your account or you can order a replacement SIM card if you would like to keep your phone numbers from the lost SIM. However, the existing data package can’t be transferred to the new SIM card.
Alternatively, you can contact customer service online or call 001-617-313-8888 for assistance.
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