I think the nearby feature of @fdroidorg is great even if I hope that I'll never have to depend on it. It lets you easily boitstrap things like @briar to other people that weren't prepared. However I wonder how would you get f-droid onto the phones of people around you? I'd imagine sending the APK over Bluetooth should be easy enough, but that assumes you have the APK handy/accessible. I'd suggest a "send f-droid to others" button in the app for this use case.
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