Actually is there any actual benefit of vowifi vs volte?
I totally understand the benefit of volte vs non volte. Haha
VoWifi or wifi calling as it is better known actually functions as Voice over
ANY available data network.
This in contrast with VoLTE which works over LTE/4G networks & VoNG/Vo5G which works over 5G SA networks.
There are 2 common ways to use it :
1) Voice call (& SMS) are routed over any Wifi network that allows wifi calling, why and how you want to use it is up to your imagination.
Common use case is for Voice/SMS in areas with good wifi coverage but poor cellular coverage.
Think some army camps, deep basement, remote office/settlements, and ships sailing in the ocean (w starlink).
Or it can be used in lieu of cellular networks, for reasons like saving battery power, reducing cellular radiation, limiting tracking etc. iPhone in particularly has great efficiency in this area, you can stay connected by wifi calling and go without charging for like 10 days in a light usage case.
2) Backup calling. This is when the sim with wifi calling turned on does not connects to a cellular network but instead use the data provided by the other sim for data traffic. This other sim can be either local or roaming sim.
This allow voice call & SMS as long as either sim has a good enough data connection.
It is useful in situation when your own carrier does not cover the area that you need to go to and you can be covered by another sim, including overseas location.
That said, Singtel, M1 & starhub all limits wifi calling from overseas IP address, so it can only be used locally, or with another SG sim roaming providing the data connection (which provides a SG IP address)
Simba don't have this limitation, but their wifi calling only works with Android.
