But, YMMV. And by all means go Japan !
In fact, there's already something similar: http://wiki.opencellid.org/wik... and probably https://github.com/SecUpwN/And...
"This app requires root access and will only run on devices with Qualcomm chipset."
That's not "for android". That's playing a Qualcomm trick with the baseband.
I also wonder if a better way might be (but I'm speculating here) to use the measured distance from the nearest cell tower (called Timing Advance), as in http://stackoverflow.com/a/137... - and couple it with a public database of known celltowers locations to spot recent "additions".
To which Ubuntu forum users massively agreed that this would make a great release name !
/usr/news/gotcha