[droopybuns]

>> 4.) It only works on GSM, i.e 2G. Hardly anyone uses that these days. (I don't know if a similar passive approach would work on 3G and 4G, it may be that only software is required in order to support more than 2G).

Do you have some data that supports this claim? I haven't gone sniffing recently- but I believe T-mobile is still wed to 2G for the foreseeable future, and internationally, 2G is still in a lot of countries. I believe one northern european telco is going to decommission their UMTS network and support both LTE & GPRS.

[conradev]

AT&T discontinued GSM nationwide: https://about.att.com/innovationblog/2g_sunset

T-Mobile is keeping it running until at least 2020: https://www.t-mobile.com/news/att-2g-iot-lifeline

edit: Wikipedia has a pretty solid list: https://en.wikipedia.org/wiki/2G#Past_2G_networks

[jstanley]

> Do you have some data that supports this claim?

Only that I don't know anyone who is happy if their phone ever connects over 2G.

By "hardly anyone uses that", I meant end users, not phone companies. I am happy to agree that 2G infrastructure still exists, it's just that most phones aren't using it.

[willstrafach]

This is Rx-only though, so the target device(s) cannot forced down to 2G.