On 2/24/19 2:01 AM, jim bell wrote:
https://www.gpsworld.com/how-to-achieve-1-meter-accuracy-in-android/
[partial quote begins]
Recent changes in hardware and standards make one-meter accuracy possible, in some cases as soon as this year. The transcript of a talk given to Android developers earlier this year, this article gives a short overview of location in smartphones, introduces Wi-Fi round-trip time technology and standards, and then explains the Wi-Fi application programming interfaces.
/By Frank van Diggelen, Roy Want and Wei Wang, Android Location, Google/
That's very relevant indeed - one-meter accuracy would remove the need to put any kind of 'flag' on top of a dead drop container. Without retroreflectors or etc. marking packages, broad searches of likely drop areas would not produce results worth paying for. Also buyers would have no need for a means of finding inconspicuous retroreflectors - just a 'really good' mobile phone. Still not "the perfect crime", but a much improved one. :o)