- Look for cool XEPs: https://xmpp.org/extensions/
- Maybe set up https://conversejs.org/ for a webchat? I am not sure if it would be a good idea to actually add it to Mastodon (even though it would definitely help with discoverability), but still, it's a cool thing
More radio related - like @DC7IA said, APRS integration? I don't think an APRS transport exist for XMPP, but it would be a pretty cool thing :D
If those were widely implemented in mobile (and desktop) clients you could use XMPP as a human-machine interface / remote control for almost anything with the intrinsic benefit of #authentication and in a way that's much easier to implement than an equivalent #web-based solution.
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