The same question can be applied to the microphone.<p>I am actually curious if there are reports about phones taking pictures of their owners without their consent to be used in ML models or anything like that.<p>It seems to be something that Google and Apple could do without much effort and without the user noticing.
Apple has status bar indicators for if an application is using the microphone or camera from a background process and when tapping the indicator the OS will try to bring it to the foreground so that you know which one, or if it cannot for some reason it tries to prompt you with the name and asks if you want to disable the app's access.<p>If your threat model includes Apple themselves it's not guaranteed that first party apps have to use the same privacy-respecting APIs, and Face ID (which does require consent) indeed has a very different UX model for when it is active (lock icons and overlay checkboxes versus status bar microphone/camera icons and red warning indicators).<p>For what little it is worth, though, it certainly feels like Apple is sincere enough in their "Privacy-focused" endeavors, that I currently don't consider Apple in my personal threat model, but as always that's a subjective judgment at best.
Currently there is no way to tell, a solution to this problem would be by default the camera is physically covered and the microphone is physically disconnected by default. In order to record you would have to physically flip a mechanical switch to uncover the camera and physically flip a switch to connect the microphone.<p>Even with physical switches to uncover the camera(s), and connect the mics, there is still the possibility that the other sensors in the phone might be able to detect the sound vibrations that the accelerometer and gyroscope are picking up.<p>This is the same concept of some electronics that you may technically have pressed the power button, but it if it is physically plugged in and has no physical switch to connect/disconnect power there is still power flowing through it (e.g. car battery, servers, speakers, monitors, switches, routers, etc).<p>If they have passive sensors in them they do not require power in order to fully function and with phones having a battery they could potentially still record data even though you powered it off if there is still residual power running through any components that can record data (e.g. like a black box in cars and helicopters, boats and other vehicles).
So this new phone I bought (oppo reno) has the front camera which needs to slide up to use. Although makes face identification unlock slightly slow(i don't use that), but I guess addresses your concern.
Android Pie is directly addressing this: <a href="https://developer.android.com/about/versions/pie/android-9.0-changes-all" rel="nofollow">https://developer.android.com/about/versions/pie/android-9.0...</a><p>Notably: "Android 9 limits the ability for background apps to access user input and sensor data. If your app is running in the background on a device running Android 9, the system applies the following restrictions to your app: Your app cannot access the microphone or camera."
No, there's no guarantee. It comes down to trust.<p>You could use a privacy slide on your cameras, but you'd still have to worry about the mic and that brings a whole other sets of complications.
There isn't a guarantee, but there are incentives for phone/platform providers to avoid spying on you in a battery-powered device. Battery life is still a primary selling point, and these companies are fighting hard to maximize battery life on your device. Turning on the camera is among the most power-hungry tasks, as it activates the image signal processor block of your SoC (which is millions of gates and a high speed transfer interface). It would be difficult to produce a competitive device which spies on its users.
An interesting concept could be for future devices to have a light wired into the hardware of your camera and microphone, so you know when either of them have power, period. Someone trying to remotely activate either device would have no way to hijack the hardware covertly.
I use some nice products from these guys:
<a href="https://objective-see.com/products/oversight.html" rel="nofollow">https://objective-see.com/products/oversight.html</a>
about a year ago, everytime I took a panorama picture, right after I took it, xPrivacy would pop up and warn me that google play services was attempting to do something and asking to allow/deny. I always denied and it didnt bother me until one day xPrivacy just went silent. It simply stopped reporting any issues and worse still reinstalling/restarting did not help. I will not detail what evasive actions I took thereafter but suffice it to say anytime I take a picture on the phone, I assume google will have it eventually.