The Natural Philosopher <t...@invalid.invalid> wrote:
> Rather that the website is written by marketing wankers, and doesnt
> relate to the real world, where 'three in touch ' is being phased out,
> and they decided to give what everybody knows is intergarted 'wifi
> calling' the 'three in touch' brand name.
>
> Sadly, the phones themselves do not mention 'three in touch' There is
> simply a menu option called 'wifi calling;' and you just switch it on
>
> Nowhere does it mention 'three in touch'.
As we said:
1. A handful of Android phones *with Three-branded firmware* support native
wifi calling in the baseband.
2. Other phones need the Three inTouch app.
As it says here:
"Although only Three customers can use inTouch, it can be used to call or
text people on any network. Likewise people on any network can call or text
you and it will come through on Three inTouch if you’re connected to it.
Three inTouch is available for Android 4.0 devices and above and iOS 6
devices and above, however it doesn’t work with the HTC One X, Huawei P2,
Sony Xperia J, iPhone 3GS, Huawei Ascend P2 or dual-SIM Android phones. It's
also not available for the Sony Xperia Z1 Compact on Android Lollipop."
I'm not sure why a handful of old phones don't support inTouch, but the
bottom line is almost any phone since 2012 does. Meanwhile:
"Great as Three inTouch is, if you're using a recent handset you might be
able to call and text over Wi-Fi automatically, without the Three inTouch
app. It's the same idea, but you can use your normal SMS and phone apps, so
it's even more seamless.
To get embedded Wi-Fi Calling on Android, you need a Samsung Galaxy S8,
Samsung Galaxy S8 Plus, Samsung Galaxy S7, Samsung Galaxy S7 Edge, Samsung
Galaxy S6, Samsung Galaxy S6 Edge, LG G5 or LG G6.
If you have one of those, you bought your phone from Three and you're
running the latest system software then Wi-Fi Calling will work
automatically and your usage will come out of your normal monthly allowance
or credit. You'll know it's working if you see the Wi-Fi Calling symbol
(above)."
The important bit here is "but you can use your normal SMS and phone apps".
In other words, Android says 'I want to make a phone call'. The baseband
says 'OK, let's route that over wifi' - so it's seamless to Android apps.
In constant, inTouch is an app you have to actively select to make a phone
call and have running in the background to receive - like Skype. This will
probably eat battery more rapidly.
If I had a wifi calling enabled phone I'd run a packet trace, but my guess
is that the backends for these two services are different. Ah yes,
https://en.wikipedia.org/wiki/Generic_Access_Network
https://ruckus-www.s3.amazonaws.com/pdf/wp/wp-wifi-calling.pdf
is essentially tunnelled GSM-over-IP (or LTE-over-IP), whereas standard VOIP
is usually SIP-based (and Skype is a proprietary protocol that Microsoft
keep changing).
Ah, it seems inTouch uses the same ports as SIP:
http://www.edugeek.net/forums/internet-related-filtering-firewall/145086-tu-o2-ports.html#post1243843
So, as I understand it, the bottom line is:
Wifi Calling = LTE over IP, in the baseband [*]
Three inTouch = SIP
Completely different ways to achieve a similar end result.
Theo
[*] it is notable that Three's Wifi Calling enabled phones all support LTE,
and probably VoLTE