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by mrjin 1661 days ago
Weren't emergency services numbers supposed to be available, not matter whether the phone is locked or not, and does not even require a SIM card? Then how come an user mode app can block calling numbers that were supposed to be available where is there is cellular coverage?
2 comments

Yes. There are lots of specific technical requirements from the FCC on this. First, even if the phone is locked, calls to 911 have to work. If there's no SIM card, calls to 911 have to work. For 911 calls, the phone's transmitter goes to full power and the receive side will attempt to connect even if the signal is too weak. If you're subscribed to one carrier and they're down, the phone has to try other carriers in range. If no talk channel is available, the cell site has to free one up, kicking off a non-emergency call if necessary. If the billing system is down in the cellular system, the call has to go through anyway. For newer technologies, VOIP has to support 911, with location info.

"Oh, we decided to divert all calls to Teams first" is just not going to fly.

Then this seems to mean that the 'Dialer' function in a lot of Android phones separates functionality at the wrong point, is that right? Having 'Dialer' as selectable should not include the ability to select what ought to be a hardware requirement to be able to dial 911. If this is true the whole pachanga falls firmly in Google's court.
that's one of my biggest reasons for not using android - i appreciate the risk that comes with "options", "choice" and "customisation".

I want my phone to work - especially during a time-critical emergency. An app crashing or bugging out is not an acceptable trade-off. That said, i have my gripes with iOS but at least Apple's thought process towards these issues is similar.

An android app isn't modal in that way. There is no "user mode". There are permissions instead, and the closest thing to "user mode" would be an app that has the 2-3 most common permissions, and no others.

https://play.google.com/store/apps/details?id=com.microsoft.... lists what Teams does or can do, and it's a long list that includes "directly call phone numbers". That means to call phone numbers without the usual indirection through the phone app, ie. Teams can replace the phone app.

So, Teams can do that because it isn't "user mode". There are others too, https://play.google.com/store/apps/details?id=com.simplemobi... is one.