We are here to help you get answers to your questions about OneSimCard phones and services.
Is there an eSIM App for Apple iOS and Android devices?
Yes. The 1Sim eSIM app is available at:
Can eSIM be used for Data, Calls and Texts?
Yes, as of March 3rd, 2020, OneSimCard eSIM can be used for Mobile Data, Voice and Texts. However, you can still use the OneSim VOIP app option with a Personal Extra Number (PEN) for additional savings on calling and texting
For DataMax eSIMs, only Data is available. However, you can use our OneSim VoIP app for cost effective voice and SMS communication.
I used a large amount of data even though I barely used data, what happened?
Each mobile data session is charged for a minimum of 10kB usage. Even if you check just one 3k email you will be charged for 10kB of usage. In some countries this can be over 30¢ per session, however in Europe and elsewhere it can be as little as 1¢. Check all rates.
Each mobile data session is charged for a minimum of 100kB usage. Even if you check just one 3k email you will be charged for 100kB of usage.
Please note: Some phones, like iPhones, Androids, and other smartphones, can access data without you even knowing it if you have data enabled. We strongly recommend checking the settings on your phone and disable mobile data roaming if you will not be needing data service. By default, all SIM cards are pre-programmed with data service enabled, once you activate your data package.
Do I need to change any settings on my phone when going abroad?
Not Really. If you are planning to use Mobile Data, you will need to enable Data Roaming on your phone. Everything else in modern phones get done automatically. However, you should ensure that the APN on the device is correctly updated when the SIM card or eSIM card is enabled.Universal, Expedition, & eSIM World SIM card types:
Name: 1SIM
APN: send.ee
Leave all other settings alone
DataMax, DataMax eSIM, & IoT Track SIM card types
Name: 1SIM (NOTE: Most IoT devices do NOT have a setting/field for “Name”)
APN : OSC (NOTE: The “O” is the LETTER O, NOT the number 0)
Leave all other settings alone
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.
How do I top up my data with eSIM?
There are two ways you can do this:
Simply go onto your web account or eSIM app and purchase a new data package appropriate to your travel needs.
Is there a mobile app that will let me recharge my account and other services?
Yes! Our myOneSim app for the iPhone devices will let you easily access many account services, such as recharging your account, checking voicemail, ordering discount voice and text plans, and much more. MyOneSim is available for download from the App store. Find more information in the Help section of your online account.
DataMax SIM cards can't be managed by myOneSim app at this time
I just activated my SIM card and can't make a successful test call. What's wrong?
If you just activated your SIM card and can not make a test call by following the instructions in the user manual, you will likely just need to power off the phone and power it back on again. The phone should automatically re-register with one of our partner networks. Remember, if you answer the test call when it rings you will be charged for the call.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.
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.
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