📱lost or stolen phone - do these in order

Apple's official steps for iPhone plus Google's for Android, combined into one order. do this instead of panic-googling it at 2am.

01
Try to locate it first, before you do anything else
do this first, before locking or erasing. you lose the location once it's off or reset
02
Lock it remotely (Mark as Lost on iPhone, Mark as lost in Find Hub on Android)
03
Don't put your phone number in the lost message
Apple's own warning: a stranger could use it for social engineering. weird but noted. (learned this one late)
04
Change your Apple ID or Google account password, from a different device
05
Report it to local police
06
Call your carrier and report it stolen
ask them to suspend the line. some plans cover a claim here too
07
Do not remove the device from Find My / Find Hub yet
removing it kills Activation Lock, which makes it way easier to resell. leave it there until this is actually resolved
08
Erase it remotely, only once you've accepted it's not coming back
09
File the insurance claim if you have one
AppleCare+ with Theft and Loss covers this on iPhone. check if your carrier plan has an equivalent

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