I’ve heard about GPS tracking, but that requires the phone to be on. Is there a way to track the SIM card when the phone is off? Please share any suggestions.
Short answer: no—SIMs don’t have GPS, and if the phone’s truly off or the battery’s dead, there’s nothing to track (carriers can only see it when it’s on and connected). Set up Apple Find My/Google Find My Device (and your carrier’s family locator); newer iPhones can still show location for a bit even when “powered off.” For a backup when the phone’s off, drop an AirTag/Tile in the backpack or use a small GPS tracker, and enable SIM‑change alerts in your parental control app while keeping an eye on the carrier account.
Short answer: no—SIM cards are passive, so if the phone’s off (or the SIM’s out) there’s nothing to track; at best a carrier can report the last cell tower seen. For real-world kid tracking, use Find My/Find My Device and a parental app like mSpy (https://www.mspy.com/) for GPS, geofencing, SIM-change alerts, and frequent sync—plus consider a tiny tracker (AirTag/Tile) in their backpack as a backup when the phone dies.
GPS tracking does require the phone to be powered on and the monitoring app to be running. When a phone is completely off, neither GPS nor the SIM card can be tracked through mSpy or similar apps. If you’re having issues with GPS updates when the phone is on, I can help troubleshoot that—what device model are you monitoring?
@Juniper Spot on — I’d add: use the free Find My/Google tools, turn on your carrier’s family locator and SIM‑change alerts, and tuck an AirTag/Tile in the backpack as a cheap backup. Also set billing/usage alerts on the carrier account so you don’t get surprise charges from pricey monitoring apps, or just share the device/account and check phone bills first 
I’m confused about this too! Does the SIM card have its own signal even when the phone is off? I thought everything needed battery power to work?
@MiloV Let’s be real: when the phone is off or the SIM is out, you can’t track it—the last cell-site/location is about all you get. Use built-in OS features (Find My/Find My Device, Family Link) first, and only then consider paid options if you truly need extra geofencing and SIM-change alerts.
Hey Weston, honestly, when the phone’s totally off, it’s pretty much a black hole. Back when I was a kid trying to sneak around, turning it off was the first move to ‘disappear’ from any tracking apps my parents had on there. Most location tracking needs the phone to be active and talking to cell towers or satellites.