Hello! I’ve created this topic as a way to track information regarding the state of Sailfish OS in the United States.
The current area of concern is VoLTE - please see the below post for information.
In addition, a historical pain point has been group MMS. I am yet to find a good solution for this.
If you have any input on this topic, please let me know!
Jolla does not seem to have any rush to implement VoLTE at the moment, which could be a problem in the US. Below, I’ve listed what the current status of multiple carriers is.
Jolla does not officially offer any products in the United States (which is a shame). You can get a Sailfish X license through certain means, but it’s against their terms.
Jolla support does not seem to care if you say you’re in the US when submitting a ticket.
Then again, even as a European, having a phone that doesn’t work in the US could sometimes be a nuisance!
Yeah, I was suspecting they may have been hopeful that I was just travelling.
You can check the status of VoLTE in the VoLTE support in SailfishOS?
Things don’t look good at the moment.
Yes, I’ve seen that. I should probably link to it. I have to wonder if they’ll get to it in a few years when European carriers start requiring it. Or if they’re just going to wait for it to be a necessity in Russia.
IMO it will be far better if the implementation comes with/from community involvement. We have some great coders around but no idea if there are any interested in implementing it.
I’ve been thinking of trying to tackle the MMS problem myself, actually. I’m not sure how I’d start though - I’ve barely worked with C/C++ and Qt. Years of experience in Dart and JavaScript/TypeScript though (as well as learning Scala). The XA2 and 10 lines support VoLTE at a hardware level, but Sony would need to update their provided drivers (which I believe they have). That (thankfully) just leaves the operating system itself as the target, but it’s unclear if anyone would be willing to help. I might look at it more later.
Probably a stupid question but is it the phone that has to support VoLTE or the OS? Got an Xperia 10 and loaded Sailfish X on it and it worked on T-Mobile about a month ago.
Both. You need “hardware” support from the phone (more specifically, the modem) and compatibility from the OS (drivers and higher-level software).
I use Sony XA2 for couple years on T-mobile USA. Not sure what VoLTE is/does, but my phone functions OK most of the time, occasionally I do experience issues with incoming calls and undelivered SMS. However, these issues happened with Xroid too.
MMS is a pain for sure. Ready to put some $$$ into kick-starter if there is a willing party to solve.
VoLTE stands for Voice over LTE. Traditional cell networks use two separate protocols for phone calls and data. 4G killed this idea and instead moves the phone calls onto the data protocol/network, leading to the name “Voice over LTE”. Devices that don’t support VoLTE just switch back to 3G/2G for phone calls, however, many carriers around the world are preparing to shut down older 3G and 2G networks, leading to the current crisis.
My phone does show 4G most of the time, on occasion (especially when traveling) it drops down to 3/2G but switching Flight-Mode on and off forces it back to 4G.
Yes, your phone tries to stay on 4G most of the time. Try taking a call, and looking at the indicator while the call is ongoing. It’ll have dropped to 3G or 2G.
One, admittedly rather geeky solution, may be to get yourself a data-only SIM and run SIP on top of that.
That’s basically what I’ve been doing for quite a while now.
It looks like in Germany they are phasing out 3G this year (Vodafone, O2) but keeping 2G available at least. For now…
You forgot the link 
https://openrepos.net/content/unmaintained/s1p
I don’t understand this … why do you need a separate hardware modem for VoLTE? If the phone already supports LTE for data (and the XA2, 10, etc do on Sailfish) and VoLTE is simply a data implementation of voice (i.e. sound is just transmitted as data packets or whatever using the LTE data protocol) then why can’t it all be done in software?
I’ve heard this may have something to do with lots of embedded devices using 2G for remote access etc.
This, in turn, may have something to do with GSM being the dominant standard in Europe back when cell phones became an everyday item. GSM wasn’t as readily adopted in the US so there may be less concern about abandoning all these legacy devices that may still rely on it.
If I remember it correctly VoLTE was always meant to be a combination of both. The modem exposes a second network interface (together with a different IP end everything) and is doing all the routing and QoS stuff while the user space applications do the SIP/RTP signalling over that interface.
But It’s been a while so I could be completely wrong about that or there may be different ways to implement VoLTE.