frequently asked questions

Do you have a question? We’re here to help! Please check our FAQ below if you have any queries.


If you cannot find your answer, please email us at and we’ll get back to you.


For information on what to do before you travel and how to activate your Interfone SIM Sticker, visit our ‘how it works’ page for a detailed walkthrough.

No, the Interfone SIM Sticker has a one-time installation and you’ll be able to use it every time you travel abroad to a country that’s a part of our network.

No. Your operator will not allow the Interfone SIM Sticker to work if your phone is SIM locked.

The Interfone SIM Sticker is compatible with most smartphones, including the Apple iPhone & Android smartphone models.


However, the Interfone SIM Sticker is currently NOT compatible with any BlackBerry device.

Your device must use a Micro or Nano SIM to be compatible.

You’ll be able to enjoy absolute convenience when you travel to multiple destinations with the Interfone SIM Sticker:


  • One SIM for everything – you won’t need to purchase another SIM at your travel destination with Interfone coverage.
  • Retain your original number for both incoming and outgoing calls, unlike a prepaid local SIM.
  • Enjoy savings when you use Interfone to make and receive calls, send and receive SMS, and use data roaming while abroad.


For information on what to do before you travel and how to activate your Interfone SIM Sticker, visit our set-up page for a detailed walkthrough.


Always remember to enable your mobile data and data roaming on your phone to ensure that you’ll be able to use mobile data in ‘AWAY’ mode.

For more information on how to set-up your device, visit

For information on what to do when you get home and how to deactivate your Interfone SIM Sticker, visit our set-up page for a detailed walkthrough at

When you have activated ‘AWAY’ mode through the My Interfone App, your device’s home screen will display:



This means that your Interfone SIM Sticker has been detected and you’re now on roaming mode.


When you’re on ‘HOME’ mode, your device’s home screen will display:



This means that your local SIM is active, and you are currently connected to your local network provider.

No. The Interfone SIM Sticker will not interfere with your local operator’s service and you’ll even be able to make outgoing international calls from our platform at cheaper rates.


If however you do not wish to use the Interfone network for international calls whilst you are in Singapore, simply dial 633 to switch it off. When you are wanting to switch the service back on dial 630.

When you make an international or roaming call, you will hear our “Connecting your call” tone and music.


This indicates that your call has been connected via Interfone.


Occasionally, the “Connecting you call” tone will only be heard partially. This depends on the connection between Interfone and the local network and won’t impact on your call quality.

If you have switched to ‘AWAY’ mode and are not connected automatically to an operator network, please try to restart you device.


If you are still not automatically connected, please manually search for an available network under your phone’s carrier settings to connect to the 3G network.


If the problem persists, you can reach us at


To activate your local service provider’s roaming services, please switch back to ‘HOME’ mode on the My Interfone App.

If you are having difficulties switching to ‘AWAY’ mode, try switching it manually.



> Settings

> Phone

> SIM Applications

> Interfone

> Switch to ‘AWAY’ mode



> Interfone STK (The Interfone icon will automatically appear on your phone)

> Interfone

> Switch to ‘AWAY’ mode

Do not remove your Interfone SIM Sticker if it does not work.


If your Interfone SIM Sticker does not work, connect to Wi-Fi and switch from ‘AWAY’ mode to ‘HOME’ mode on the My Interfone App and restart your phone.


If the problem persists, you can contact us at

You’ll be able to track your usage through the My Interfone App or the My Interfone Portal where you can log in to view your call usage, manage your account credit and check the call rates.


You’ll also be able to top up your account balance if you are using a prepaid account.


To access the My Interfone Portal, visit

Making Calls


Just call as you normally would from your phone’s keypad. Simply dial the country code and your recipient’s number. No additional codes are required.

Before the call gets connected, you will hear a beep to confirm that the call is going through our network.



To make a call after installing the Interfone SIM Sticker, simply dial the country code and recipient’s number into your phone’s keypad as you would normally.


When you make international calls, there are no additional codes required and we’ll route them through the Interfone network to make sure you get the best rates.

All your locals calls will still go through your local operator as normal.


We’ll only route your call through Interfone’s network when you dial an overseas number.

Yes, you’ll receive calls made to your original number, and will be able to make outgoing calls through that number too.


All you need to do is dial as you would normally from your keypad.

When using our services, you will seldom experience any difference between our service and your home operator.

When using the Interfone SIM Sticker, the first leg of the call is a GSM connection.


Once the call reaches the Interfone network, we’ll convert the call to a VoIP call.

Call forwarding is automatically activated when you switch to ‘AWAY’ mode.


In order to receive calls as per usual when roaming, call forwarding must be set up before you travel. When call forwarding is done, the cost of receiving an incoming call will typically be significantly lower compared to your normal operator.




If you do not activate call forwarding or activate it only after you arrive at your destination, you will still be able to receive incoming calls with Interfone’s low rates.


However, your home operator will recognise that you’re travelling – and all your incoming calls will be recognised as an international call, resulting in a higher incoming call rate charged by your operator compared to Interfone’s incoming call.

Your call forwarding might still be activated if you are unable to receive any calls.

Follow these instructions to switch call forwarding off:


> Settings

> Phone

> Call Forwarding

> Change ‘Call Forwarding’ to ‘OFF’


> Settings/Call Settings

> Call Forwarding

> Disable Call Forwarding

Data Roaming

The network you connect to will be dependent on your destination country’s infrastructure, and your phone model.

Check if mobile data and data roaming have been enabled on your device.


Some operators may switch it off by default and you will not be able to connect to data if so.


To enable data roaming and set up your APN settings, please follow these steps:



> Mobile Data

> Enable Mobile Data

> Mobile Data Options

> Enable Data Roaming

> Select Mobile data Network

> Change APN to <Interfone> (case sensitive), leaving the username & password field empty.



> Settings

> Mobile Networks

> Access Point Names

> Add

> Change name and APN to <Interfone> (case sensitive)


We accept payment by Mastercard and Visa.

Yes, it’s legal. Interfone is holding a SBO license from IDA in Singapore and we work with the best providers to provide you a fully legal service.

Your individual employees can sign up for a personal account. They will be responsible for their personal usage and billing.

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