It Depends. Long winded answer ensues.
[QUOTE=Vino7373;4057713]Can you still be tracked if you have turned off your regular cell phone?[/QUOTE]It can be done, but one has to ask, why would they want to do that? I know most reading this forum are paranoid to some degree, so this reply may not dissuade fears, but knowledge is power.
Modern cell / smartphones that do not have a user replaceable battery, never turn totally off. Never. We shut them down. They are always doing something. Always. With older phones with user replaceable batteries, one could simply remove the battery. No battery, no power, phone can't do anything.
One way to prove this is to set an alarm on your phone to go off in a couple minutes, then shut it down. At the alarm time, one of two things will happen. Older smartphones without the latest and greatest security updates will wake up and sound the alarm. Wow, that's unsettling.
If the alarm doesn't sound, it doesn't mean the phone is "off". It means, for most phones, it's in ultra low power mode. It's still keeping track of the time, and your alarm, among other things. A lot of other things. In modern phones, these background tasks use micro-AMP, not milli-AMPs. The processors and operating systems are energy scrooges, designed that way to maximize battery life while still scraping dirt about people's activities. Our personal lives and habits are extremly valuable to marketers and advertisers. That's all Google and Facebook are, in my opinion. Simply huge people intelligence sifters, and marketing engines, in my opinion. In my opinion, I believe that their mantra is "our personal lives are for sale," but I digress. For another day.
Turn the phone back on if the alarm didn't go off at the appointed time, and on 99.9% of them, as soon at it boots up, nearly instantly, the alarm will sound. It will stop once you log into your phone. Again, not good. It indicates that the phone is never off. In either scenario, it's still keeping track of time, and who knows what else. Well, I know, but that's for another topic and day. What else the phone is doing depends on the phone brand, model, operating system, and all kind of alien super-brainiac engineering crap that goes on in our daily lives for which we've given up our control without knowing it.
The biggest power draw on any phone is the screen. It's like a big light bulb with its energy demands. All the other things a phone does in the background for system purposes use extremely small amounts of battery power compared to lighting up that screen. So, can a phone be triggered while it's off to track someone? Yes, but, and there is always a but, there needs to be a reason, and they need to specifically know which phone to subvert. Always remember, a smartphone is always listening, documenting, and reporting while turned on. Even in airplane mode, it is still doing that, recording, just not transmitting the data until airplane mode is off. Of course, unless one needs to be tracked real time, it doesn't matter. Our phones are always going to send back to the mothership what it has gleaned about us once it can reestablish contact, and that's all that's needed for investigatory purposes. Real time tracking is rarely needed except for national security purposes.
If one is concerned about being tracked real time, look at the battery percentage of the phone, shut it down for a half hour (I know it's hard but really, we can do it), leave it on a desk or table, screen side down to reach room temperature, and then see if it has any any warmth after the cool down interval (and don't charge your phone because it generates heat). If it seems warmer than the table or desk it's sitting on, it's possibly being busy while "turned off". It's consuming more energy than being in ultra low power mode, in my opinion. Also, when you turn it back on, if there is a noticeable drop of more than 1% in the battery usage (assuming one's battery isn't at end of life, aged, and unhealthy, and dies rapidly to start with), then one has to ask why that is happening? It's what they call a clue.
The best way to check the temperature after the cool down interval has passed is with one of those cheapo infrared temperature devices. Put the phone on the table screen side down, leave it on for a few minutes, then measure the temp of the back of the phone when running. Then shut it down, put it back on the table screen side down, and let it get to room temperature. It will take a half hour or so. Then while still shut down, check the temperature of the back side again while still resting on the table. Then take the temperature of the table it's resting on a few inches away, and they should be very close, and best case is the phone is cooler than the table. Metal backs on phones can cause the phone to read a bit lower temperature than the table. That's a good thing. Again, too much warmth suggest that the phone it being a bit more active when shut down. "Danger Will Robinson. Danger".
So, what can one do to go dark other than leaving the phone behind? Purchase an RF shield bag to put your phone in. These are also known as Faraday bags. Get one with very high ratings, and one that totally, and I mean totally, seals. Get one that is large enough for your device, phone, tablet, etc, that totally seals, shut down the device, stick it in the bag. And do this for every device you bring along. You'd be surprised at the people that shut down and bag their phone, but not the iPad in the trunk, or GPS stuck to their windshield. While a GPS doesn't transmit, and yes, there are some that still use them, a windshield GPS records coordinates when turned on. Always. For those that desire, it's relatively easy to plug a GPS into a computer, extract the data, and plot routes, with dates and times, on Google Maps. Same thing for tablets that are not cellular enabled. They can't transmit while not connected to WiFi, but they will transmit all they have gleaned from their sensors, Bluetooth, and GPS receptions once they are.
Anyway, once devices have been shut down and bagged, and since they cannot now receive or transmit, it won't be recording data while it's turned off. Just be sure to go a good distance from your destination before taking them out of the bag and turning them back on. I'd recommend shutting down devices a good distance away from the destination or travels one wants to obscure, putting them in a bag, and not powering up until you are back at the same location where the devices were shut down. When the device re-contacts the mothership, and it will, there will be no new data to report, other than the shut down, and restart. Plausible deniability is a good thing. The story is up to you.
Well if you're that concerned
[QUOTE=BBC386;4058480]Are one smart mofo, thanks. I am going to invest in a bag LOL. Being a doomsday prepped I feel like I should have already owned one. Is it wise to use an app and delete the app after each usage? I know this doesn't do much in the case of Apple as they're store keeps recently downloaded apps in que without being able to clear that list. Please advise.[/QUOTE]That your phone is sharing your Mac address and or IP address when it's powered off. Then you're paranoia won't rest that you can very well be downloading Trojans and other malware when you download an application. If I really wanted to track your phone / computer that's how I'd do it.