after that can work fully offline. So after initial setup, no network needed.
Thanks, but well aware, right above:
Did I miss the instructions to be sure to download the needed offline data before the Typhoon hits (e.g. OsmAnd)?
Previously:
OsmAnd~, and a couple GigaBytes of offline data files
(Ref. Quelles sont pour vous les 10 meilleures applications à avoir sur F-Droid? - #5 by anon46495926 )
However, I still feel a little paranoid seeing network traffic every time I start OsmAnd, after turning off every related setting I can find. And some maps and wikipedia data files get updates almost once a month. Not paranoid enough to use Airplane mode, but a little. 
Briar
over Bluetooth, so no internet needed.
Always get a LOL imagining people Briar’ing within Bluetooth range. 
But yeah, maybe it has applications behind barriers at protests and front lines, if you forgot your short range radios.
Bigger LOL from naming: Why didn’t they call it Passing Wind?