Stacks and Flows

Relay.app

Human-in-the-loop workflow automation with AI steps, approvals, and a focus on cross-team collaboration over raw integration count.

other freemium Updated 2026-05-11
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Pros

  • Human-in-the-loop steps are first-class — approvals, edits, and AI-with-review are baked into the canvas, not bolted on
  • Cleanest AI step UX in the category — model picker, prompt, structured output, all inline without a separate AI module
  • Native collaboration model: workflows have owners, reviewers, and per-step assignees like a doc tool
  • Built-in Gmail, Google Calendar, Slack, Notion, HubSpot, Linear deep integrations (not generic OAuth wrappers)
  • Free tier is genuinely usable for solo and small-team workflows

Cons

  • Integration count is small compared with Zapier or Make — a few hundred apps, not thousands
  • Cloud-only, no self-host, no on-prem story for regulated buyers
  • Pricing climbs once you need more than a couple of AI-credit-style steps per month
  • Branching, loops, and error handling are less mature than n8n or Make
  • Smaller ecosystem — fewer templates, fewer community recipes, fewer hires who already know it

Best for

  • Teams whose workflows need a human to approve, edit, or send before something goes out
  • AI-heavy automations where the LLM step is the point, not an add-on
  • Ops, RevOps, and CS teams who live in Gmail, Slack, HubSpot, and Linear

What it is

Relay.app is a workflow automation tool built around the premise that the interesting workflows in 2026 are not pure machine-to-machine pipes — they are human-in-the-loop sequences where AI drafts, humans approve, and software ships the result. Founded in 2022 and out of public beta in 2024, it sits in a category Zapier and Make were never designed for: workflows that pause, wait for a person, and resume.

The pitch is straightforward: AI steps are a first-class block, approvals are a first-class block, and assignment to a teammate is a first-class block. You get a small but deep integration set (Gmail, Calendar, Slack, Notion, HubSpot, Linear, Salesforce, Airtable, and the usual webhook escape hatches) instead of the 7,000-app catalog Zapier sells.

Who it’s for

Relay is a strong fit for teams whose work product is a draft a human signs off on. Sales reps who want AI to write the follow-up but won’t send it unread. Customer success teams routing AI-summarized tickets through a tier-1 review. Marketing teams scheduling content with editorial approval baked in. Anyone whose Zaps already contain a “wait for human” hack.

It’s a poor fit for high-volume, headless automation (Zapier or n8n win there), for workflows that need exotic integrations, and for anyone who needs to self-host or keep data on their own infrastructure.

Strengths

  • Human steps as primitives. Approve, Edit, Assign, and Wait For Person are real workflow blocks with their own UI. The competitors have nothing equivalent — they have webhooks and timeouts.
  • AI steps that don’t feel grafted on. Pick a model, write a prompt, choose structured output, pass it downstream. The DX is closer to a real AI editor than to “AI by Zapier”.
  • Collaboration model. Workflows have owners and editors. Steps have assignees. The mental model is closer to Notion or Linear than to “integration platform”.
  • Deep, opinionated integrations. The Gmail/Calendar/HubSpot/Linear/Slack adapters do more than generic OAuth — they expose actions Zapier doesn’t bother to model.
  • Free tier you can actually use. Real workflows fit inside the free plan; you upgrade when you genuinely need to.

Weaknesses / Watch out

  • Catalog ceiling. A few hundred integrations, not thousands. “Does Relay connect to ___?” is much more often a no than with Zapier.
  • No self-host. Cloud-only. Regulated buyers and ownership-minded teams will hit a wall here.
  • AI step costs. Once a workflow runs many times a month, the AI credits add up; the value-per-run is higher, but so is the bill.
  • Branching and loops are still maturing. Anything that needs deep conditional logic or large fan-out is more comfortable in Make or n8n.
  • Ecosystem is young. Templates, community recipes, and hireable Relay operators are all thinner on the ground than for the incumbents.

Best paired with

  • Gmail and Google Calendar — the integrations Relay invested in most.
  • HubSpot, Salesforce, or Linear — where the human-approval pattern earns its keep.
  • A second tool for high-volume, headless jobs — many teams keep Relay for the human-touch workflows and route volume work through n8n, Make, or Zapier.

Lock-in score

Medium. Workflows are not portable to other platforms — there is no JSON export that another tool can ingest, and the human-step primitives have no equivalent on Zapier, Make, or n8n. The mitigation is the same as for Zapier: keep Relay for what it is best at (human-in-the-loop AI workflows) and put portable, headless jobs on a more open platform from day one.

Verdict

Recommended for the workflow it was built for. If your real work is “AI drafts, human approves, software ships”, Relay is the cleanest tool on the market and worth paying for. If your work is “trigger fires, action runs, nobody looks at it”, Zapier, Make, or n8n will serve you better and cheaper. Pick by the shape of the workflow, not by the marketing.

Sources

FAQ

Is Relay.app free?
Relay.app is freemium. Check the official pricing page for current tiers and limits.
What is Relay.app best for?
Teams whose workflows need a human to approve, edit, or send before something goes out AI-heavy automations where the LLM step is the point, not an add-on Ops, RevOps, and CS teams who live in Gmail, Slack, HubSpot, and Linear
What are the main downsides of Relay.app?
Integration count is small compared with Zapier or Make — a few hundred apps, not thousands Cloud-only, no self-host, no on-prem story for regulated buyers Pricing climbs once you need more than a couple of AI-credit-style steps per month
Who should use Relay.app?
Human-in-the-loop workflow automation with AI steps, approvals, and a focus on cross-team collaboration over raw integration count. See our review for the full pros and cons.