Due to the recent events envolving planes and FBI, I was wondering. Changing SIMs (so IMSI) is an easy task. Change IMEI with some knowledge I believe its too. There are some tutorials on IMEI changing on rooted android, I dont known if actually works, suppose yes: http://www.technostall.com/how-to-change-imei-number-android/ http://www.plusdroid.com/Blogandnews/how-to-change-restore-imei-no-on-androi... Knowing we can get TMSI / IMSI (sometimes) via RTL-SDR software + proper dongles: http://www.rtl-sdr.com/rtl-sdr-cell-phone-imsi-tmsi-key-sniffer/ https://ferrancasanovas.wordpress.com/cracking-and-sniffing-gsm-with-rtl-sdr... And knowing the IMEI is used / exchanged with the network before authentication is granted to a certain phone (network can block IMEIs, so they are sent/exchanged) Do someone know if is it possible to check if the original IMEI was really changed and is not being exchanged with the provider, by using RTL-SDR + proper device to sniff the frequency? http://www.rtl-sdr.com/ regards, --Virilha