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Cross-app Comments

Cross-app comments point every podcast app at the same canonical discussion thread using <podcast:socialInteract>, so a conversation about an episode is not trapped inside whichever app the listener happens to use.

Why it matters

Comments are the classic platform lock-in: whoever hosts the thread owns the audience. Naming the thread in the feed inverts that — the discussion has an address, and any client can read it and post back into it.

It is also where Podcasting 2.0 and Nostr meet in practice. A podcaster can root the thread in a Nostr note and let listeners reply from any Nostr client or podcast app that speaks it.

How it works

<podcast:socialInteract> can appear at channel or item level, more than once. protocol and uri are required — uri is the root post of the thread, protocol names the system it lives in. accountId is recommended, with accountUrl and priority optional; lower priority wins when several tags are present.

protocol="disabled" is a deliberate signal that public comments are off, which apps should honour rather than inventing their own thread.

Sources

Who implements it

12 of 136 apps in the Podcast Index directory support Social Interact — 9%.

  • AntennaPod
  • Blubrry
  • Castopod
  • PeerTube
  • Podcastindex
  • PodToo
  • Podverse
  • PowerPress by Blubrry
  • Sovereign Feeds
  • TrueFans
  • Up Next
  • Vodio

From the Podcast Index apps directory, as of 2026-08-17.

Heard on the show

16 moments across 14 episodes.

  1. E120 · 3 Feb 2023 · Chop & Drop

    • 1:31:03Cross app comments hosting & moderationchapter

  2. E116 · 6 Jan 2023 · Cryptotarians

    • 15:34Cross app comments, and chat, and boostagrams, Oh my!chapter
    • Cross-app comments (Mitch & Alecks)timeline

  3. E113 · 16 Dec 2022 · Substance Dualism

    • 1:10:08Abandoning cross app comments?chapter

  4. E112 · 9 Dec 2022 · Respect The Splits

    • 44:57Where are Cross App Comments?chapter

  5. E77 · 11 Mar 2022 · Is that a minipub in your pocket?

    • Cross app comments vs boostagramsshow notes

  6. E75 · 25 Feb 2022 · Liquidifying for Love

    • 56:14Cross app comments vs. boostagramschapter

  7. E74 · 18 Feb 2022 · Confetti Canon

    • 1:08:51Activity pub/ cross app commentschapter
    • 1:18:05Cross App Comments Contchapter

  8. E65 · 10 Dec 2021 · Billions Served

    • Cross app comments wtf?show notes

  9. E164 · 19 Jan 2024 · Let's Get Local

    • 49:38publishing I mean, I'm publishing cross app comments.transcript

  10. E130 · 21 Apr 2023 · For All The Drummers

    • 50:34way we implement cross app comments. It isn't in fact, thetranscript

  11. E125 · 10 Mar 2023 · Wolf Nuts

    • 1:10:30cross app comments, and then I'll be happy with everythingtranscript

  12. E114 · 23 Dec 2022 · Protoflexible

    • 54:25I've been doing on the cross app comments from I've been spenttranscript

and 2 more episodes, back to E110 (11 Nov 2022).

Show all 16 moments across 14 episodes

  1. E164 · 19 Jan 2024 · Let's Get Local

    • 49:38publishing I mean, I'm publishing cross app comments.transcript

  2. E130 · 21 Apr 2023 · For All The Drummers

    • 50:34way we implement cross app comments. It isn't in fact, thetranscript

  3. E125 · 10 Mar 2023 · Wolf Nuts

    • 1:10:30cross app comments, and then I'll be happy with everythingtranscript

  4. E120 · 3 Feb 2023 · Chop & Drop

    • 1:31:03Cross app comments hosting & moderationchapter

  5. E116 · 6 Jan 2023 · Cryptotarians

    • 15:34Cross app comments, and chat, and boostagrams, Oh my!chapter
    • Cross-app comments (Mitch & Alecks)timeline

  6. E114 · 23 Dec 2022 · Protoflexible

    • 54:25I've been doing on the cross app comments from I've been spenttranscript

  7. E113 · 16 Dec 2022 · Substance Dualism

    • 1:10:08Abandoning cross app comments?chapter

  8. E112 · 9 Dec 2022 · Respect The Splits

    • 44:57Where are Cross App Comments?chapter

  9. E111 · 18 Nov 2022 · Pod Molly

    • 8:13cross and it's called cross app comments. I'm awaiting for twotranscript

  10. E110 · 11 Nov 2022 · Paws & Claws

    • 35:58cross app comments, which has zero traction. But sincetranscript

  11. E77 · 11 Mar 2022 · Is that a minipub in your pocket?

    • Cross app comments vs boostagramsshow notes

  12. E75 · 25 Feb 2022 · Liquidifying for Love

    • 56:14Cross app comments vs. boostagramschapter

  13. E74 · 18 Feb 2022 · Confetti Canon

    • 1:08:51Activity pub/ cross app commentschapter
    • 1:18:05Cross App Comments Contchapter

  14. E65 · 10 Dec 2021 · Billions Served

    • Cross app comments wtf?show notes

From chapter titles, show notes, the PC 2.0 Timeline and the clip notes. Where those say nothing, from the episode transcript — which reaches further but only records that a word was said. 214 of 266 episodes have curated notes; 177 moments come from transcripts.