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Superhuman rebuilt its mobile apps and wired every inbox into AI assistants — the email client is becoming a suite.
Comparison · Comms
Slack vs Threema
A side-by-side editorial comparison of Slack and Threema — release velocity, themes, recent moves, and the top alternatives to consider.
Slack vs Threema: at a glance
What is Slack?
Slack raises the Marketplace bar back to ten installs while the agent platform consolidates.
Slack's developer platform runs two tracks. The agent build-out has produced a spark roughly every two weeks since June — MCP client, a skills plugin targeting Claude Code and Cursor, and Slack Code — and now has a consolidation date attached: assistant_view is deprecated in February 2027, replaced by an Agent Sessions API. The second track is platform administration and tooling, and this window belongs to it: Marketplace submissions again require at least ten installed active workspaces, held throughout the review, after a period at a lower temporary threshold. The CLI has shipped three times since late July.
What is Threema?
Threema's feed is privacy positioning, and this week it had to explain an outage
The feed carries essays far more often than releases. The newest entry is an incident post explaining a series of DDoS attacks that made the service partly unavailable across a Tuesday evening and Wednesday morning, plus the measures taken since. Around it sit position pieces — declining WhatsApp interoperability under the DMA, arguing anonymity belongs in system architecture — with one genuine Threema Work feature, easier tag management in the Management Cockpit.
Slack vs Threema: editorial side-by-side
Slack
6.3COMMSCOLLAB
Slack raises the Marketplace bar back to ten installs while the agent platform consolidates.
◆ Current state
Slack's developer platform runs two tracks. The agent build-out has produced a spark roughly every two weeks since June — MCP client, a skills plugin targeting Claude Code and Cursor, and Slack Code — and now has a consolidation date attached: assistant_view is deprecated in February 2027, replaced by an Agent Sessions API. The second track is platform administration and tooling, and this window belongs to it: Marketplace submissions again require at least ten installed active workspaces, held throughout the review, after a period at a lower temporary threshold. The CLI has shipped three times since late July.
◆ Where it's heading
The install requirement moving back up is a distribution decision arriving in the middle of a platform push, and the two point the same way. Slack is making it easier to build agents and harder to list one, which favours developers who already have distribution — existing workspace tools and vendors — over a new app hoping the Marketplace supplies its first users. Combined with the assistant deprecation and the Agent Sessions API, the platform is narrowing on one agent surface and one class of builder rather than widening the funnel.
◆ Prediction
The threshold is described as a return from a temporary lower bar rather than a new policy, so the open question is what replaces the Marketplace as the discovery path for an app that cannot reach ten workspaces on its own. These entries do not answer it.
Threema
5.0COMMS
Threema's feed is privacy positioning, and this week it had to explain an outage
◆ Current state
The feed carries essays far more often than releases. The newest entry is an incident post explaining a series of DDoS attacks that made the service partly unavailable across a Tuesday evening and Wednesday morning, plus the measures taken since. Around it sit position pieces — declining WhatsApp interoperability under the DMA, arguing anonymity belongs in system architecture — with one genuine Threema Work feature, easier tag management in the Management Cockpit.
◆ Where it's heading
Threema is competing on stance rather than feature velocity: most posts argue why its architecture is the right one, not what changed in the app. The DDoS post fits that pattern in a different register — availability is the one axis where an architecture argument is settled by operations rather than by essay. Actual product news continues to surface mainly on the Threema Work admin side.
◆ Prediction
Expect the next posts to return to privacy positioning, with any concrete shipping news most likely being another Management Cockpit administration feature. Whether the DDoS mitigations hold is not something the entries let you judge yet.
Alternatives to Slack and Threema
Other Comms products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Slack or Threema.
Chatwoot
Chatwoot is building an AI-first support platform, with Captain gaining audience targeting and macro automation reaching the keyboard-native workflow.
Signal Desktop
Signal adds granular notification controls: badge content, muted threads, restore defaults
Zoho Cliq
Zoho Cliq 7.0 bets on AI conversation summaries and Neat hardware to close the gap with enterprise messaging platforms
Krisp
Krisp adds deepfake detection and expands Voice Translation as its Call Center AI platform deepens enterprise compliance tools.
Netcore Cloud
Netcore's recent entries are blog content, not product releases — the signal is a BFSI and ecommerce vertical sales push.
See all Slack alternatives → · See all Threema alternatives →
Recent activity from Slack and Threema
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 15d agoSlackUpdated installation requirement for Slack Marketplace apps
- 16d agoSlackCLI adds app-approval status checks and custom app icons
- 27d agoSlackAnnouncing Slack Code ⚡
- 27d agoSlackAgent Sessions API replaces assistant_view, deprecated Feb 2027
- 1mo agoThreemaDDoS Attacks on Threema
- 1mo agoSlackAnnouncing the Slack MCP and Skills Plugin ⚡
- 1mo agoSlackCLI adds manifest diff and a Block Kit preview command
- 1mo agoThreemaMessenger Interoperability: Well-Intended, but Bad for Data Privacy
- 1mo agoThreemaEasier Tag Management in the Management Cockpit
- 2mo agoThreemaWorld Emoji Day: Our Emoji Pet Peeves
- 2mo agoThreemaWhat We’re Working On
- 2mo agoThreemaAnonymity at the System Level – The Ultimate Privacy Protection
Frequently asked questions
What is the difference between Slack and Threema?
They serve adjacent needs but don't currently overlap on shipped themes. Slack is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Slack better than Threema?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Slack is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.
What are the best alternatives to Slack?
Top Slack alternatives in Comms are ranked by recent ship velocity. Browse the "Slack alternatives" section above for the current picks, or visit /alternatives/slack for the full list with editorial commentary on each.
What are the best alternatives to Threema?
Top Threema alternatives in Comms are ranked by recent ship velocity. Browse the "Threema alternatives" section above for the current picks, or visit /alternatives/threema for the full list with editorial commentary on each.