There is some level of opt-out, but it doesn't work reliably, and your app might still get killed.
Even the K9 team had issues with that, and many other open apps did so, too. I've been trying to work some kind of push messaging into the IRC bouncer for which I wrote an Android client, but the issues with legality (I can't just connect to a third party without explicit opt in), API keys (people who host an IRC bouncer don't want to register with Google), liability (I don't want to relay all messages through a server of my own), Google's ToS (I can't just publish an API key for everyone to use), confidentiality (I can't actually put content into the FCM messages due to legal issues), etc are so problematic that it's basically stalled everything.
I've filed a complaint with the EU, this seems like the only option I've got left. I can't tell everyone running a bouncer to register with Google, I can't relay all messages of all IRC users through a server of mine, and I can't bake in a Google API key into IRC bouncers (as that violates Google's ToS)
Even the K9 team had issues with that, and many other open apps did so, too. I've been trying to work some kind of push messaging into the IRC bouncer for which I wrote an Android client, but the issues with legality (I can't just connect to a third party without explicit opt in), API keys (people who host an IRC bouncer don't want to register with Google), liability (I don't want to relay all messages through a server of my own), Google's ToS (I can't just publish an API key for everyone to use), confidentiality (I can't actually put content into the FCM messages due to legal issues), etc are so problematic that it's basically stalled everything.
I've filed a complaint with the EU, this seems like the only option I've got left. I can't tell everyone running a bouncer to register with Google, I can't relay all messages of all IRC users through a server of mine, and I can't bake in a Google API key into IRC bouncers (as that violates Google's ToS)