One exception: The Serval mesh project is specifically meant to address the situation of no Internet or cell access. Caveat: it hasn't been updated recently and the Google app store no longer has it. It is still available via F-Droid. It looks like it may be useful if one has a working network that is not connected to the Internet (or has a very poor connection). https://servalproject.org https://servalpaul.blogspot.com/2018/11/serval-chat-ios-port-finally-emerges... https://f-droid.org/en/packages/org.servalproject/ On Thu, Sep 2, 2021, 11:07 Sean Donelan <sean@donelan.com> wrote:

Another reminder....

Walkie-talkie apps on smartphones, like Zello, still require working Internet access. They don't work without cell or wifi service and internet access. Zello keeps reminding people, it REQUIRES internet access; but people don't get it.

https://www.reuters.com/article/factCheckNew/idUSL1N2Q31SN

Only about 5% of households have a NOAA/Weather radio with battery backup (slightly higher in tornado alley).