Anything may be possible, but it would have to be built into a module to do so, like echolink is. I wasn’t sure what Zello was so I had to look it up. It looks like it may be more of a commercial solution. ORP focuses more the Amateur Radio side of things. If someone was to spend the time working on other VOIP integrations it would likely be on something like Allstar network and IRLP. Hope that helps.
73,
Aaron – N3MBH / WRFV871
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