It sounds like the issue is that Google didn't specifically exclude the emergency number for {user's country/province} from being sent to third-party calling apps. These apps can register to handle calls for legitimate reasons.
Ah, so MS Teams is a phone app and Android couldn't decide which of the installed phone apps has precedence. Are there similar issues around WhatsApp, Signal,...?
Android use the default "Calling app" when the user wants to make a call. MS Teams is one such "Calling app": the first time you install any other than the default shipped with your phone, you (the user) are presented a choice to choose which one you want to use. After that, Android remembers your choice.
This means in this case, MS Teams was configured as the default "Calling app" and the issue could have been prevented at 2 level:
- at the Android level, if the user dials an emergency number, don't use the default "Calling app" and use a special "safe" calling app to ensure the call succeed even if a user-installed app is misbehaving.
- at the MS Teams level, allow emergency calls to succeed even if the user isn't logged in (or any other reason that could prevent an emergency call to be made, really).
As for WhatsApp, at least on my device, it's not a "Calling app", and as such cannot override the default calling app. I don't have Signal installed to check.
How exactly do you check your "calling apps"? I'm on Android 12 and have a list of "Phone apps". However, the only other app listed there (besides "Phone") is a VOIP app I specifically installed to make alternative phone calls with. Signal, WhatsApp, Telegram and not listed, even though I've used all of them to call other users on the respective apps.
First: I used "Calling apps" because that's how it's displayed on my Android 8 phone. The actual naming isn't consistent across Android versions, so yours is probably named "Phone apps". That's located in the settings, and again the exact way to access it varies according Android versions, manufacturer and whatnot (which is an endless source of pain to guide end-users by the way).
To appear there, apps have to declare they are phone apps and handle the proper calls (an "Intent" in Android jargon) when the system receive a request to make a phone call. WhatsApp, Signal and Telegram do not do that: you are only able to initiate a call when already inside the app.
I don't know about Android 12, but on Android 11 it's in Settings > Apps an notifications > Defaults Apps.
This is where you choose which app you want as default for phone, browser, messages, etc
> at the Android level, if the user dials an emergency number, don't use the default "Calling app" and use a special "safe" calling app to ensure the call succeed even if a user-installed app is misbehaving.
That doesn't make sense, the user has to pick the app to dial with before they have an interface to enter the number.
Assuming that your hypothesis is correct: No. Signal doesn't have that permission and I think whatsapp doesn't either, and neither signal nor whatsapp can be signed out in the first place.
I wouldn't go so far as calling my post a hypothesis, it was like a guess. Another guess, wouldn't the fact that neither WhatsApp nor Signal are causing the same issues hint at MS Teams being the culprint?
Teams does the wrong thing, there's no question about that. But it's not clear to me that the Android core is unable to check that the phone app does the job, and has to trust it blindly.
> Why on earth would you want apps to be able to intercept calls on a phone?
Because there are housands of users even on HN that WANT apps like Signal to be able to manage secure encrypted calls like a first-party app with the same rights. Basic software freedom and all that.
I want Signal, Slack, Teams, my apartment buildings intercom system, etc, to be able to present their own native incoming calls through the same dialogs that regular calls come through. But not at the cost of potentially not being able to call emergency services...
> I want Signal, Slack, Teams, my apartment buildings intercom system, etc, to be able to present their own native incoming calls through the same dialogs that regular calls come through. But not at the cost of potentially not being able to call emergency services...
Understand that calling emergency services on VoLTE is essentialy VoIP as well - noone here disagrees that this is a horrifying bug. But the issue with this bug is not the APIs that allows VoIP apps to integrate into call system (after all, those APIs also make Signal/WhatsApp/Skype/Teams calls work over systems like smartwatches, Android Auto and Bluetooth car integrations) but the fact that Android somehow missed the fact that a buggy app can stop a call.
Incoming calls or manually dialling a number directly through the respective app is a different matter, but when you click a stored number in your contacts list, or a phone link in your browser or another app, or anything like that, that app just hands the number to the OS and basically says "please call this number for me".
If you want to allow alternative VOIP apps and things like that to exist, at that point the OS must allow routing that number to any app that claims it can handle (outgoing) phone calls.
Yeah sure, and for most things it's fine if things break, irritating and bad press, but fine. Things like calling emergency services can never be allowed to break. It must have fallbacks, if it even needs to be allowed to be overridden in the first place.
According to this old bit of documentation (https://android-developers.googleblog.com/2013/05/handling-p...), the usual way of intercepting call requests should already handle emergency calls ("Note that the system broadcasts NEW_OUTGOING_CALL only for numbers that are not associated with core dialing capabilities such as emergency numbers."), so it'd be interesting to know what went wrong in this case (and why only on Android 10 and newer), but until then it's hard to say more and it's all just speculation…
There are many reasons why an app would want to be notified of a call taking place - e.g., a music app could use this event to auto-pause playback, Teams might set the availability status to "busy", etc.
The question is what should happen if such an app takes an excessively long time handling the event. In this case, the OS should not wait for the app and should directly go on making the call. The bug seems to be that the OS did wait, so a misbehaving app can effectively block phone calls by e.g. going into an infinite loop.
> Why on earth would you want apps to be able to intercept calls on a phone?
My daughter enlightened me to this recently.
Android devices are not phones. They are computers that come preinstalled with some apps, one of which is a phone app. Importantly: They are not marketed as PHONES. They are marked as "Smartphones". Just search for the word "phone" on the websites of any major Android device manufacturers.
The distinction is important.
Be careful when punishing children from "using the phone". Today, this means that they cannot use the app called "phone". This incident is a stark reminder that "phone" is an app today, not a physical device.
You are right that many younger people (and not only younger people) primarly think of those little black rectangles as computers with several apps. As you say, in their minds, making voice calls in the classical way just happens to be one of those apps rather than the device's primary function.
But you are dead wrong about the word "phone". It still means those little black rectangles. If you primarily think of those little black rectangles as computers (or social media machines) then the word "phone" has shifted meaning to match that. If you punish a child by banning them from "using the phone" you will absolutely get the horrified reaction you'd expect.
Of course words vary in meaning throughout the world and maybe "phone" really does mean the classical phone app in your area, or in your daughter's social group. But that's exceptional, regardless of age.
I'm basing the definition on the usage of words by the companies which manufacture and market the devices. See the usage of the words "phone" and "smartphone" on the LG, Samsung, and Xiaomi websites.
Apparently, the "phone" in "smartphone" is about as relevant as is the "fun" in "funeral".
The evolution of the meaning is even more obvious in at least one other language: Japanese borrows the English word "smartphone" for those, but uses "denwa" (with its own kanji) for non-smartphones.
Sure, I agree with that. (But also, what marketer would miss an easy opportunity to include "smart" in their product's description.) I was just talking about your last paragraph.
Sure, I'll accept that. But the point isn't that the devices _are_ something specific, rather, the point was that the device _isn't_ considered a phone by the manufacturers. "Phone" is one function of the device, but no even its major selling point.
There is a fallback call flow for emergency calls in cases where the phone cannot register properly but it would be nice to be able to overlook missing bureaucratic elements and just save lives, and that’s what “Emergency Calls Only” signifies, but it probably only activates when normal flow fails.
