We are here to help you get answers to your questions about OneSimCard phones and services.
What is required to use the OneSim VoIP mobile application?
OneSimCard VoIP requires you to order a compatible Personal Extra Number (PEN). Most of the PENs we offer are OneSim VoIP enabled. You also need to have an Android phone with software version 8 or higher, or Apple device (iPhone, iPad, iPod Touch) with iOS 6.1 or higher.
Once you have an active OneSim VoIP enabled PEN, you will be able to see the option to create a OneSim VoIP account in the My SIM Cards menu of your online account. NB: YOU MUST create the 1SIM VoIP account in your account online on the "My SIM Cards" menu. Simply purchasing a PEN and downloading the mobile app DOES NOT create the VoIP account.
How does OneSimCard compare to the international roaming from the largest US carriers?
OneSimCard can help you save a lot of money on international roaming abroad over large domestic carriers. Check out these rate tables to compare international roaming offerings from AT&T, Verizon,  and T-Mobile.Â
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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.How does OneSim VoIP work when the call is received?
When someone dials your OneSim VoIP enabled Personal Extra Number (PEN), the system will first check if your OneSimCard phone is registered with the OneSim VoIP app on a Wi-Fi network. If it is registered, the call will be sent using VoIP. If the OneSim VoIP app is not running or it is not registered on a Wi-Fi network, then the call will be sent using the standard OneSimCard roaming network and charged our standard roaming rates.The battery in my phone does not last long? It got fully drained during the flight to Europe. Why?
There can be a number of reasons why a battery does not hold a charge. Excluding the possibility of it being a faulty battery, there is another important factor to consider. If your phone is not registered on a roaming network, the battery will drain very quickly as the phone is constantly searching for a network to register on. So, if you get on a 6 hour flight and do not turn the phone off, or put it into airplane mode, by the time you land at the airport your battery will be drained and you will not be able to call back home.
The same thing will happen in those areas with spotty or weak signal network coverage - the battery will drain very fast. It is always a good idea to have an extra battery with you when you travel abroad.
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Will a OneSimCard international SIM card work with my mobile phone?
OneSimCard will work with almost any unlocked GSM tri-band or quad-band cell phone. A partial list of compatible cell phones that we have tested can be viewed here.
If you need to unlock the phone, we suggest contacting your carrier or phone manufacturer for unlocking information or services.
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.
If you are still unsure whether your cell phone is compatible, contact support or purchase an international cell phone and SIM card bundle from us, which all come preloaded with our international SIM card, $10 balance and OneSimCard Apps Installed.
Do international cell phones purchased from OneSimCard come with a warranty?
Unless otherwise noted, all phones sold on OneSimCard.com come with our standard 90-day replacement warranty. This warranty covers any mechanical defects, but does not include damage due to Acts of God, neglect, water damage, or other intentional or unintentional abuses of the phone. OneSimCard does offer extended warranties available for purchase.
How to activate and set up the mobile data service on your mobile device or tablet?
Do you offer an eSIM option for iPhones, Androids or Tablets?
Yes. The OneSimCard eSIM option is available for use with iOS and Android phones, smart watches and even Windows tablets.
eSIM is not a physical SIM, but rather a program that can be downloaded to eSIM compatible phones and device.
The list of supported devices includes:
iOS:
Apple iPad models with an eSIM:
Learn more about eSIM compatibility on the eSIM page.
 Note: iPhonesmanufactured for the Chinese Market have 2 physical SIM card slots and are not eSIM capable. Pixel 3a can't use eSIM if the phone was purchased in Japan, or if bought with Verizon or Charter service.Can I disable per MB/Pay-As-You-Go data usage for DataMax SIM cards
Yes you can. On your online account, in the "My SIM cards" menu, you will see a section labeled "Select SIM Card." In that section there is a line labeled "Use w/o Plan." If you do not want to use data on a per MB/Pay-As-You-Go basis, and only consume data with a data plan, set this to "Off."
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