GrapheneOS functionality with Tmobile satellite texting

Marcus_A

Hey all,

I see that Tmobile is rolling out a partnership with spacex to use their low orbit satellites to relay texts in areas without cell coverage. Does anyone know if this will be supported by GOS? Or would using GOS make it so I can’t use that section of service?

de0u

Marcus_A There has been recent discussion of this topic: https://discuss.grapheneos.org/d/17291-new-emergency-sos-locator-feature

spammerofspam

I'm interested in finding this out too. Based on reports, this has not rolled out to everyone yet. Some people have reported (on stock OS) having a satellite option under their SIM settings, while others, including my friend running stock OS on T-Mobile, do not have any such option (yet).

Has anyone seen such an option on GrapheneOS? Would such an option ever appear on GrapheneOS? Ideally, has anyone had it working on stock and then switched to GrapheneOS? That would be the best test.

Marcus_A

Last I heard the timeline from Tmobile was to roll this out to androids early 2025 and the option that showed up for people on stock android was the using garmin satellites? I guess my question is weather GOS will have satellite capability at all?

spammerofspam

de0u I think that works differently than the T-Mobile solution, doesn't it? That appears to be about the Google satellite texting feature, which, at the very least, differs from the T-Mobile feature because the T-Mobile feature isn't limited strictly to Google Pixel phones.

In any case, it does look like the T-Mobile feature probably isn't available on GOS. Or, it at least, the toggle / submenu is missing. My friend has a stock P9P, and it now has a "Satellite" option now in the T-Mobile SIM menu. I was invited into the T-Mobile satellite beta, but my GOS phone is missing the satellite option in that menu, so I'm assuming I won't be able to use it.

JollyRancher

spammerofspam
If you have access to another phone (ideally the same model) and use a physical SIM, try popping it into the stock phone, enabling satellite if it is offered, and then putting the card back in your GOS phone.

No promises that it would work but it would be interesting to see if it does.

de0u

spammerofspam I think that works differently than the T-Mobile solution, doesn't it?

In various technical senses, clearly it is a different solution. However, in terms of whether or not it depends on a proprietary vendor app, it seems to be the same. So I think the first and third paragraphs of what I wrote in the other thread likely apply:

My understanding is that the feature is not part of AOSP, i.e., it depends on a proprietary Google app. I don't think the GrapheneOS project has yet looked into what it would take to get that app running, and it's possible that it can't be done. For example, if the app uses the "Integrity" (attestation) system to check that the app is running on Google's OS, it won't run on GrapheneOS.

[...]

It is possible that eventually this sort of thing becomes common enough (and cheap enough) that an open implementation will become available, and it's also possible that the GrapheneOS team might get Google's app to run. But I am unaware of any plans or even efforts along those lines.

So if tomorrow there is an announcement of a special limited-access satellite program between, hypothetically, U.S. Cellular and Hughes, and that solution requires a proprietary app from U.S. Cellular, I suspect it won't work on GrapheneOS in any predictable time frame.

I do think it's plausible that once satellite LTE is common and everybody is doing it the same way, for example including roaming agreements, then it will be usable on GrapheneOS.