Find My iPhone only works if it was switched on before a device went missing, so this is worth doing today rather than after the fact.
Turn it on
- Open Settings and tap your name at the top.
- Tap Find My.
- Enable Find My iPhone, then enable Find My network and Send Last Location.
Locate a lost device
Go to icloud.com/find or open the Find My app on another Apple device signed into the same family setup, select the missing device, and choose Play Sound, Mark As Lost, or Erase.
If it is stolen
Mark it as lost immediately, contact your carrier to suspend the SIM, and report the theft to the police with the device location if available.
