I sort of had the opposite experience. My pixel 5’s fingerprint reader worked about 20% of the time. It was so bad. I’ve actually had a much better experience with the Pixel 7’s in-screen one. It’s probably 90% successful. Before my Pixel 5, I had a OnePlus 6, and that one was like 99% successful.
My work uses Dell servers, which have this thing called iDRAC, which is a separate embedded system that can manage the server even if the server is off. The iDRAC can turn the server on even if it’s off. Even if the server is off, you can log into the iDRAC and check the status of the server and see if there are any hardware issues, see if the server is on or off, update the firmware, etc.
This sounds like overkill for a phone, but I wonder if they are doing it this way, with a separate embedded system. If they did, it could potentially use only a small fraction of the battery power Android uses. It could potentially last weeks or even months on a charge.
More likely, it’s booting a separate image - not unlike recovery mode - when it turns off, and like you said, it’s not actually off. But it would be interesting if it has a separate embedded system just for tracking the location even when the OS is powered down.
Ideally they’ll let you turn off this feature regardless of battery implications, because it sounds like a security concern if your location can be tracked even if your phone is off.
Edit: wow, I worded my first section really poorly. But I’m to tired to fix right now. Hopefully you understand what I was saying.
I used to be an Android device developer back in the Lollipop days. I compiled the various images myself, including the bootloader, recovery, and the Android OS. I can say with 100% certainty that at least back in the Lollipop days, and at least on the vast, vast majority of devices (a device could theoretically change this, and I don’t know everything about every device ever released), the battery percentage that shows up when the phone is off is part of the bootloader, not Android. It’s a separate image entirely.
You most likely are flashing the bootloader, recovery, and OS all in one step. They can be combined into one image and all flashed at once. I doubt the Android bootloader would be able to boot Linux, but tbh, that’s not my area of expertise, so I could be wrong.
Google is switching the Pixel 9 to an ultrasonic fingerprint reader (www.androidauthority.com)
[General question to the Android community] Have you given up on the audio jack, or do you still only buy devices that have it?
(Posting this here rather than !askandroid as it’s a quite general question)...
Small Phones are Dead and We Killed Them (www.youtube.com)
Android 15 will let you find your Pixel 8 even when it's off (www.androidpolice.com)