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Comparison · Comms
OpenPhone vs Slack
A side-by-side editorial comparison of OpenPhone and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
OpenPhone vs Slack: at a glance
| Feature | OpenPhone | Slack |
|---|---|---|
| Sector | Comms | Comms, Collab |
| Velocity score | 0.0 | 6.3 |
| Sparks · 30d | 0 | 1 |
| Top themes | business voip, ai phone agent, call routing, smb communication | agents, a2a, mcp, slackbot-skills |
| Last editorial update | 6mo ago | 3d ago |
| Website | — | Visit → |
What is OpenPhone?
OpenPhone turns Sona into a deployable front-line AI agent with transfers and per-scenario instructions.
OpenPhone is hardening Sona, its AI phone agent, into something businesses can actually put in front of customers. Sona can now route calls to the right teammate when a human is needed, and admins can give it custom instructions per scenario (lead qualification, cancellations, booking) with templates to start from. Around it, the call flow builder keeps maturing: multiple routing setups with quick switching, in-place inbox switching during flow construction, and a Go-to Step primitive for cleaner branches.
What is Slack?
Slack now hosts any A2A agent without Slack-specific code.
Slack's developer channel is almost all agent plumbing. On 10 November Slack became an A2A (Agent2Agent) client: a team hosts its own agent, publishes an Agent Card, and Slack calls it when people talk to it, with no request URL, event handling or Slack-specific logic. This follows Slackbot skills managed through Web API methods, a Slack CLI that points coding agents to the Slack MCP server, and a new requirement that Work Objects embeds allow the slack-mcps.com frame ancestor.
OpenPhone vs Slack: editorial side-by-side
OpenPhone
0.0COMMS
OpenPhone turns Sona into a deployable front-line AI agent with transfers and per-scenario instructions.
◆ Current state
OpenPhone is hardening Sona, its AI phone agent, into something businesses can actually put in front of customers. Sona can now route calls to the right teammate when a human is needed, and admins can give it custom instructions per scenario (lead qualification, cancellations, booking) with templates to start from. Around it, the call flow builder keeps maturing: multiple routing setups with quick switching, in-place inbox switching during flow construction, and a Go-to Step primitive for cleaner branches.
◆ Where it's heading
The core bet is an AI-handles-first-contact, humans-handle-edge-cases pattern. Each Sona release is closing a deployment-blocker (instructions, transfers, free trial), while the call-flow tooling underneath is getting more flexible so AI and human routing can coexist in one config. Plan-tier expansion (call hold on Starter) suggests OpenPhone is also chasing volume in the lower segment.
◆ Prediction
Expect Sona to gain CRM-aware context (caller history, deal state) and outbound use cases — proactive callbacks, scheduled follow-ups. Pricing for Sona usage is likely to evolve from a flat add-on toward usage- or outcome-based once volume appears.
Slack
6.3COMMSCOLLAB
Slack now hosts any A2A agent without Slack-specific code.
◆ Current state
Slack's developer channel is almost all agent plumbing. On 10 November Slack became an A2A (Agent2Agent) client: a team hosts its own agent, publishes an Agent Card, and Slack calls it when people talk to it, with no request URL, event handling or Slack-specific logic. This follows Slackbot skills managed through Web API methods, a Slack CLI that points coding agents to the Slack MCP server, and a new requirement that Work Objects embeds allow the slack-mcps.com frame ancestor.
◆ Where it's heading
Slack is lowering the cost of putting outside agents in front of its users: first skills as code, then MCP pointers for coding agents, now a standard protocol in place of the Slack app model for agents. The platform is positioning itself as the place where agents built anywhere meet the people who use them.
◆ Prediction
Expect more A2A follow-ups, such as agents appearing in Slackbot or skills surfaces and richer Agent Card features, given how fast the agent releases have stacked up since October.
Alternatives to OpenPhone and Slack
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 OpenPhone or Slack.
Twilio
Twilio's voice AI stops cutting callers off mid-sentence, using its own turn-taking model.
Salesmsg
Salesmsg adds call-back requests and a one-click Emergency Stop for all outbound texts.
Element
Element 1.12.35 follows the call picture-in-picture release with one desktop storage fix.
Krisp
Krisp moves call transcripts and live captions to cloud transcription in KrispCX 2.84.4.
Misskey
Misskey 2026.11 ships: a leaner start script, and Node.js 22 no longer boots.
See all OpenPhone alternatives → · See all Slack alternatives →
Recent activity from OpenPhone and Slack
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 4d agoSlackBring your A2A agents to Slack ⚡
- 8d agoSlackWork Objects embeds require the slack-mcps.com frame ancestor
- 10d agoSlackSlack CLI 4.13 tells coding agents about Slack MCP and Skills
- 10d agoSlackSlack Skills Plugin installs in Claude Code from its own marketplace
- 12d agoSlackUpdated low-usage submission criteria for Slack Marketplace apps
- 15d agoSlackSlack CLI 4.12.0, the fourth CLI release in October
- 1y agoOpenPhoneCall hold now available on Starter plan
- 1y agoOpenPhoneTransfer calls from Sona to your team ⚡
- 1y agoOpenPhoneControl how Sona responds in different situations
- 1y agoOpenPhoneCreate multiple call flows, and switch back and forth easily
- 1y agoOpenPhoneImproved navigation for call flow building
- 1y agoOpenPhoneBuild cleaner call flows with the Go-to Step feature
Frequently asked questions
What is the difference between OpenPhone and Slack?
They serve adjacent needs but don't currently overlap on shipped themes. Slack is currently shipping more aggressively (velocity 6.3 vs 0.0), 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 OpenPhone better than Slack?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Slack is currently shipping more aggressively (velocity 6.3 vs 0.0), 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 OpenPhone?
Top OpenPhone alternatives in Comms are ranked by recent ship velocity. Browse the "OpenPhone alternatives" section above for the current picks, or visit /alternatives/openphone for the full list with editorial commentary on each.
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.