Android: Where does android store system properties key/value
Device Serial

I have several devices sharing the same serial (namely the phantastic 0123456789ABCDEF), so I've been looking for a solution as well a few years ago, and found it. Of course, it requires a rooted device.

adb shell
su
mount -o remount,rw /system
vi /system/etc/install-recovery.sh
# edit, save and exit
mount -o reount, ro /system


And here comes the line to add to /system/etc/install-recovery.sh to make the magic happen:

echo -n NEWSERIAL123 &gt; /sys/class/android_usb/android0/iSerial


Of course, replace NEWSERIAL123 by the serial you want the device to use. After the next reboot, this should be in effect.



Device IMEI

As for the IMEI, you'd better not touch that. Legal issues – apart from the fact that different brands deal with it differently.