Apparently even airplane mode might not necessarily protect you (though I don't claim to know how this works in the internals of iOS): > Furthermore while the

Apparently even airplane mode might not necessarily protect you (though I don't claim to know how this works in the internals of iOS): > Furthermore while the IMSI is not transmitted often a silent SMS or a failed call will induce the phone to transmit its IMSI or TMSI also in and out of airplane mode while registering on the network. https://en.wikipedia.org/wiki/Talk%3AIMSI-catcher https://en.wikipedia.org/wiki/Talk%3AIMSI-catcher