docbert

2 of the 3 Australia mobile carriers, Vodafone and Optus, geo-block WiFi calling and only allow it from Australia. You can use a VPN to overcome this, but you can't use an on-device VPN (at least on non-rooted Android) as Wifi calling bypasses the VPN. I have a separate Wifi network at home that routes over a VPN back to Australia, and can use that to make calls from Optus (haven't tried Vodafone).

At least initially they claimed they did this to prevent fraud/etc, although I suspect it has as much to do with forcing people to paying roaming rates as anything...

As I said above, I'm not aware of any US carriers that do this.

draver

I’ve chatted with several different US Mobile reps, and they stated that IMS is currently in beta testing and agree that it should work for my plan, equipment, and intended use. I have tested it in the US, and it worked well, mixing a Verizon US Mobile (Shared Warp 5G) voice line with a T-Mobile data line. It is not WiFi calling and requires two distinct lines, and any two lines should work as long as the device is capable. I’m currently using 2 T-Mobile lines in China right now, but you can mix & match carriers. Unfortunately most Android phones are not capable of IMS due to lack of dual sim, dual standby functionality. As I mentioned, I have been using it for well over a year internationally, and with excellent results overseas. One of the best roaming features is you may call another US number that is also roaming internationally while you are roaming, and neither line is charged.

i screwed up my testing plans by not confirming my 911 address and making a WiFi call prior to my trip departure. I was chatting again this morning with 2 US Mobile reps and thy can’t override that requirement. I had just switched plans the morning of my departure to the Shared Data plan and forgot about the 911 side of it.

serpens

I'm sorry; you've lost me. Would you elaborate on both "confirming my 911 address" and how that omission caused a problem? Thanks.

bwiadca

My Tmobile form US let me call free US and Canadian numbers while on wife outside of US. Few times I've got calls from US when I was 'outside' of wifi and Tmobile charged me 10c per minute for that call (I think that was for incoming calls). For outgoing calls without wifi they charge 25c be it US number or European/Asian number.
I spent hours on the phone when working in KSA (with the customer in US). Because I was on wifi the calls were free.

Speaking of Tmobile. How to add ESIM to iPhone 14 or 15 when you want your primary number to stay and have ESIM from another country as a secondary number and internet provider when you are in that country?

draver

My prior experience with T-Mobile was that after defining a 911 address, it was still required that you complete a WiFi call while in the US for international roaming WiFi calling to be activated. This seems to also be a stipulation for that service with US Mobile. I asked the reps at USM if they could override the system in my case, but they said they cannot. I wonder if it is part of the 911 network details, but don’t really know. I have told USM I would be testing this over their services on my current trip and they seemed eager to learn the results from an actual user. I switched to a plan that has this capacity only a few hours before departing the States, and forgot about the system confirming my registration. I suspect the 911 system has some very rigid service requirements, but don’t know for sure. I”ll be traveling again in late March and will have an opportunity to wring this out at that time.

edited to add: I searched the Verizon website and found this under 911 references. copy/paste.

• “You must accept the Wi-Fi Calling Terms and Conditions when they are displayed.
• You must confirm, update or enter the US address when it displays (this is where you want emergency personnel to go if you call 911).

Note: iOS smartphones must be connected to the Verizon network in the US. You can't turn on Wi-Fi Calling outside of the US.”

serpens

Thank you. I had not heard of this before, or I had forgotten it. I suppose it makes sense.

And thanks for the additional info. My takeaway of the part in red is to turn on Wi-Fi calling promptly upon establishing service (with any carrier, MVNO or otherwise).

There was an interesting sequence of events. Apparently I opened this thread before you edited your post, then you edited your post while I was reading it, then I clicked Quote, and there was more of your post quoted than I had just read. It was weird until I figured it out.

draver

Have your new cellular service assist you on installing an esim for their service. When 2 esims are active, you can choose between them which is to provide data, which will be for voice. These can easily be switched endlessly without any issues. IOS will prompt you when you first restart for those setting, then you can change them in: Settings-Cellular, then choose which line is Cellular Data, which is to be used as Default Voice Line. It is easier to do than to explain it actually.

TGarza

Thanks for the information. I know someone who has Visible by Verizon and will be using IMS on a trip to Asia. As a precaution I told the person to test WiFi calling with Visible.

draver

serpens & TGarza,

I highlighted the last sentence in red since it addressed my shortfall. Please be sure and make a successful Wi Fi call after completing your 911 address info and approving their terms on your phone. To be safe I’d also call my phone on WiFi only from another house or cellphone. I’m pretty sure I had registered on my previous US Mobile plan for the WiFi side. I guess it reset when I switched to a new plan.

I’m pretty disappointed by my failure to do this simple step mainly because I’m beginning a 24 day cruise around Asia without the perfect opportunity to test my new feature. I do still have all my T-Mobile features & lines for service though.

serpens

You have my sympathy. I have had similar realizations in hindsight, and they are very frustrating.

pseudoswede

Can you imagine truly non-technical people trying to figure this out? No wonder Verizon & AT&T makes $$$ charging $10/day for the "convenience factor."

I suppose I'm also fortunate that most everyone I would need to call in foreign lands (while overseas) have either Facebook Messenger or WhatsApp.

TGarza

I was carrying 2 phones on trips abroad using a phone with the local sim as my hotspot to avoid the daily carrier fees. $10 becomes $13 after the taxes and fees.

The 2 phone approach is an option for those with a locked phone.

bwiadca

When my mom was visiting me not long ago, she had to call her neighbor in Europe to check something. I gave her my tmobile cell phone and she called for about 10 minutes. The next billing cycle I was hit with $60 one call fee! I was furious. Called tmobile customer service and inquired about it. My plan clearly states 25 cents to international locations. The customer rep told me that the call that was made was to landline not mobile network! I've asked to be transfer to her supervisor, explained to the guy what had happened and he removed the charge. All those mobile providers play dirty games.
Before I had $10 a month unlimited calls to Europe (landlines and cell phones), since I was able to teach my parents how to use iPad with FaceTime I was able to cancel that add on to my plan. Now I think it cost $15/mo.
Also, all of my customers in Europe, ME, South America and Asia use WhatsApp to call me. I don't remember when was the last time that someone has called me on my actual cell phone number. They don't want to pay and I don't want to pay

draver

Update on my current trip experiments.

I am in Thailand now, and just put my US Mobile line in the Voice Line position on my i15 PM, and in less than a minute, it displayed “Using Cellular Data”. This is an indication that it is using my T-Mobile data line as a pseudo WiFi service under the IMS feature. I made 2 calls to other US numbers on my account and left voicemail messages. These should only be possible over the pseudo WiFi “IMS” dual sim function. These calls were recorded for those lines, and I was also able to retrieve them, complete with transcriptions.

I don’t really understand how this occurred, since my WiFi calling on the US Mobile line hasn’t been activated for WiFi calling. I am able to confirm that my line is the one dialing out since iPhones show the line in use for making calls. There is no roaming on, or even available for this line on my plan. That it is working, may be a very useful shortcut for travelers in the States & internationally.

This is interesting for several reasons, but primarily because a $10 a month line from US Mobile may be the perfect companion to your data roaming line for free IMS calls to US numbers from a dual sim phone. This gives me 2Gb of extra data per month on Verizon in the US, a spare phone number, and a seemingly bulletproof non roaming carrier for IMS setup overseas. No more hunting for a second carrier that WON’T work to enable IMS !

I’ll be in Asia a few more weeks, and will continue to experiment with this discovery. I welcome any questions, comments, or suggestions for alternate configurations.

draver

Rather than add an edit to a long post, this is my current preliminary findings as it relates to the original thread subject of 12-30-23.

Since I now seem to mysteriously have WiFi calling enabled, I have been able to make 2 WiFi calls on my US Mobile line to foreign numbers while roaming in Thailand. I have successfully called Thai Airways over IMS (T-Mobile Data), and also an independent WiFi network. These calls were to +66 XXXX numbers, which is the country code for Thailand. I was able to switch to the English menu and step through the first few options in a call over a minute long. This seems to confirm what I had been told by their rep as an included free feature.

I intend to explore this feature as much as possible in the next few weeks. If it is what it seems, it will be a real game changer for travel communications. Imagine having a low cost alternate line that gives not only international free WiFi calling, but also may be used with or in lieu of IMS for US WiFi calling.

In summary if you don’t care about the details, here is what MAY be possible.

Be able to set up a dual sim phone for free calling to and from US number prior to departure.
Set up the same phone for free calls to foreign numbers while in a foreign country.
Have a phone with Verizon voice & text and 2Gb of Verizon data for the US @$10 a month, inc. taxes and fees.
Retain the use of any roaming data service you prefer for overseas use.

As serpens alluded to very early on, this may all be “Too Good To Be True”, but time will tell. It certainly is interesting to explore.