VoWiFi

1. What is VoWiFi?

Voice over WiFi (VoWiFi) is the ability to make and/ or receive calls & SMSes over your WiFi connection.

2. What is the benefit of VoWiFi?

Voice over WiFi (VoWiFi) allows customers to receive and make calls over a WiFi network with a Yoodo (by CelcomDigi) mobile line when mobile signal is limited or absent. It is a simple direct dial, as long as customers have a compatible phone and have enabled WiFi-Calling on their phone. 

Additionally, customers will be seamlessly connected in an active call when moving from weak 4G coverage to a strong WiFi signal.

3. What are the differences between Voice HD (VoLTE) and VoWiFi?

Voice HD relies on the 4G LTE network. It offers superior voice quality where customers can still enjoy high-speed mobile data connectivity while simultaneously being on a call.

On the other hand, VoWiFi uses the WiFi connectivity to make high definition (HD) calls. In circumstances where 4G coverage is not available, customers will be seamlessly transferred to VoWiFi service, hence improving overall call reliability where a strong WiFi signal is available.

4. What are the prerequisites for customers who want to enjoy VoWiFi service?

1. Customers must be on active Voice HD (VoLTE) service
2. Compatible device which supports VoWiFi
3. Mobile device is equipped with USIM
4. Strong WiFi signal: VoWiFi has high dependency on WiFi network, hence call quality may be compromised in crowded areas or venues where WiFi signal strength is weak (e.g. malls, hotels, airports, cafes).

5. How do I enable VoWiFi on my mobile device?

Different phones may have different steps to enable VoWiFi.

In general:

From your phone, click at Settings > Mobile Network > Enable Wi-Fi Calling/ VoWiFi.

Android:

From your phone, click at Settings > Mobile Network > Mobile Data > Wi-Fi Calling > Enable Wi-Fi Calling/ VoWiFi.

If your phone does not have this option, it may not support VoWiFi. Additionally, ensure that your phone is updated with the latest software/ firmware.

6. Can I deactivate VoWiFi?

Yoodo (by CelcomDigi) will provision VoWiFi service to customers who are VoLTE active and have compatible devices. Yoodo (by CelcomDigi) will not perform de-provisioning on our end. However, if you are not interested in using VoWiFi, you can disable ’WiFi Calling’ in your device settings.

7. Am I able to use my mobile line to make calls and send SMS if I disable VoWiFi on my device?

Yes. However, these activities will rely on other network service signals such as your mobile network or Voice HD services.

8. Will VoWiFi utilize the data quota allocated to my mobile plan?

VoWiFi calls do not use any data quota allocated to your mobile plan. However, it will utilize the data quota from the WiFi data allocation.

9. Will I be charged for VoWiFi?

There are no additional charges for VoWiFi. It will utilize the voice minutes in your current plan.

10. Can I make an international call (IDD - International Direct Dial) via VoWiFi?

Yes, you can make an international call or international direct dial (IDD) with VoWiFi and will be charged according to the rate plan or standard rates.

11. Can I use VoWiFi at public WiFi hotspots (i.e. hotels, airports, campuses & restaurants)?

You should be able to use the service with any WiFi signal. However, this is subject to the WiFi service provider as voice calls can be blocked by the WiFi provider using certain router configurations.

12. Can I receive VoWiFi calls while having an active browsing session on a WiFi network?

Yes, you would be able to make VoWiFi calls and browse at the same time as long as you are connected to a WiFi network.

13. Can I make a video call with the WiFi network?

Yes, you should be able to make a video call with VoWiFi if your device supports video calls.

14. Can I send and receive SMSes over the WiFi network?

Yes, you should be able to send and receive SMSes over WiFi.

15. Can I use VoWiFi while roaming?

VoWiFi whilst roaming is currently not available.

16. Will call waiting and call holding work during an active VoWiFi call session?

Yes, call waiting and call holding features are expected to work as per normal.

17. Can I activate/ deactivate call forwarding when on a VoWiFi call?

Yes. Call forwarding is a voice call feature, and it will work as per normal (just like a call made over VoiceHD).

18. Why am I not able to make calls via VoWiFi even though I am connected to a WiFi network?

There are a few possible reasons:

• VoWiFi requires an adequate Wi-Fi signal strength (with a minimum bandwidth of 25 kbps) before initiating the automatic connection to WiFi Calling. You can try to move to an area where the signal strength is stronger.
• If the WiFi network has a captive portal (Eg. Starbucks which requires a login), you may have to launch the browser and sign in to the network with the provided username/ password.
• For public WiFi networks, the provider may have policies in place to block WiFi calling services.
• For private WiFi networks (e.g. company WiFi), the location may have policies in place to block WiFi calling services.
• Your device may not fulfil the prerequisites for VoWiFi service.

19. What are the minimum requirements for the WiFi network?

The minimum wireless LAN bandwidth for VoWiFi is 25 kbps.

20. How do I know whether I am connected to VoWiFi?

Different device brands will have different indicators for you to identify whether VoWiFi has been enabled on your device. In general, an icon will appear on the top right of the along with the WiFi signal logo. Refer below example of screenshot to identify active VoWiFi on Android phones:

21. How do I activate VoWiFi? Do I need to call Yoodo (by CelcomDigi) to activate VoWiFi?

Customers who have been selected (based on device compatibility) will be automatically provisioned for VoWiFi. When the device has been provisioned, you will be notified via SMS.

22. What happens if I switch to a new smartphone?

Given that you still use the same mobile number, you will still be provisioned with VoWiFi service if VoWiFi is enabled on your device. However, depending on the new device model acquired, you may or may not be able to enjoy voice call services over WiFi. 

23. Are there any specific plans that I need to be on to enable/ provision VoWiFi?

Eligibility for VoWiFI is not dependent on the mobile plan subscription. Yoodo (by CelcomDigi) will provide a service to selected customers according to their device readiness.

24. I am using MultiSIM on a VoWiFi supported phone. Can the MultiSIM make and receive calls over the WiFi network?

If VoLTE is provisioned on the MultiSIM, you will be able to make and receive calls over VoWiFi.

25. If my line was barred due to zero balance, can I still enjoy VoWiFi?

If your line is barred, suspended, or terminated, you will not be able to make a call.

26. Recently I switched to an eligible device for VoWiFi. However, I realized that VoWiFi service on the smartphone is not available. What should I do?

You can check on the below prerequisites:

• Ensure that you are VoLTE active.
• Ensure that your device supports VoWiFi service.
• Ensure your device has been upgraded to the latest firmware.
• VoLTE is switched ON in the device settings (Steps to enable VoWiFi may differ subject to device models).
• Ensure that VoWIFI or ‘Wi-Fi calling’ is enabled on your device.