Linq: The iMessage API for AI Agents, Explained
Linq is a messaging API that lets AI agents and apps text people over iMessage, with RCS, SMS and voice alongside it. Developers rent phone lines from Linq, and their software sends and receives blue-bubble messages through them. If you know the name from digital business cards, it’s the same company. Linq started out selling digital business cards and lead capture to sales teams, then turned to AI agents after an assistant called Poke adopted its messaging API and went viral.
The quick answer: Linq is the infrastructure under many of the AI assistants you text, including Poke and Tomo. It’s built for conversations people start, not cold outreach, and it raised a $20 million Series A in February 2026. A disclosure first: we make Carly, which gives businesses AI phone and texting agents, so there’s some overlap with what Linq’s customers build. We’ve kept to checkable facts and linked them.
Linq at a glance
Checked against Linq’s site, docs, terms and status page on November 12, 2026.
| Linq | |
|---|---|
| What it is | An API for iMessage, RCS, SMS and voice, built for AI agents and consumer apps |
| Headquarters | Birmingham, Alabama |
| Founders | Elliott Potter (CEO), Patrick Sullivan (CTO) and Jared Mattsson (president), all ex-Shipt |
| Funding | $20 million Series A, February 2026, led by TQ Ventures with Mucker Capital |
| Plans | Hobby free (20 contacts), Pro from $260 a month, Enterprise custom |
| Message fees | None. Linq sells flat monthly plans |
| Developer access | REST API, TypeScript, Python and Go SDKs, a CLI |
| Compliance | SOC 2 Type II |
| Built on it | Poke, Tomo, Lindy, Soar, Arden and Orchid, according to Linq’s site |
From business cards to iMessage infrastructure
Linq’s first product was a digital business card that doubled as a lead-capture tool for sales teams. The card shop is still on its website, with a digital card listed at $14.99 when we checked. According to TechCrunch, the company “pivoted a few times” before launching an API in February 2025 that let businesses message customers natively in iMessage. Within eight months, Potter said, Linq had doubled the annual recurring revenue it had taken four years to build.
Then came Poke. In spring 2025, the Interaction Company of California came to Linq with an AI assistant that lived in iMessage. Potter told TechCrunch the startup said it didn’t have a CRM, “but we really want to use your API.” Poke went viral when it launched that September, and Linq was flooded with AI companies asking for the same thing. Potter described the choice as “do we stay a spoke of this wheel, or do we build the hub?” Linq chose the hub.
The numbers Linq gave TechCrunch at the time of its Series A: customers up 132% from the previous quarter, more than 30 million messages a month, 134,000 monthly active users reached by its customers’ agents, and net revenue retention of 295% with zero churn. Its site now says it has handled more than 950 million messages for more than 1,000 teams. Those are company figures.
Linq has also distanced itself from its sales roots. Its own guidance for AI assistants says Linq “is not CRM software for sales teams,” and its developer docs tell builders not to use iMessage for cold outreach.
Who builds on Linq
Linq’s customer list reads like a directory of the consumer AI assistants people text. Poke, Tomo, Soar and Lindy all appear in Linq’s iMessage agent store, Tomo’s team is quoted on its homepage, and posts it features say Arden and Orchid are built on Linq too. So when you text one of those assistants, Linq is often the company passing your message along.
Tomo’s endorsement is the most specific: “Linq has been our closest infrastructure partner, helping us scale Tomo to hundreds of millions of messages.” For more on the assistants themselves, see our roundups of Poke alternatives, Tomo alternatives and AI assistants you can text.
How Linq works
Apple doesn’t offer a public iMessage API. Linq runs the service on what it calls “real Apple infrastructure” in its own data centers. Its status page has logged a power failure at one data center and maintenance on network hardware, which gives a sense of the physical setup behind each line.
For developers, Linq looks like a standard messaging API:
- Lines. Your account gets one or more phone numbers. Each has a status, active or flagged, and a reputation score.
- Sending. You post a message with a recipient. If you leave out the sending number, Linq picks the line for you: it reuses the line the conversation is already on, opens new chats on the healthiest line, and moves people off a flagged one.
- Protocols. Linq picks iMessage, RCS or SMS based on what the recipient’s phone supports.
- Webhooks. Inbound messages, delivery updates and line status changes arrive by webhook.
The feature list covers most of what iPhone users expect: group chats of up to 31 people, reactions, read receipts, typing indicators, voice notes, contact cards, iMessage apps and live location. Linq has also added payments. With Agent Pay and an Agentcard integration, an agent can take a payment or spend on a customer’s behalf inside the conversation. There are official SDKs for TypeScript, Python and Go, and a CLI for sending a first message from a free account.
Linq pricing
Linq’s pricing page has three tiers.
| Plan | Price | What you get |
|---|---|---|
| Hobby | $0 | Up to 20 contacts through the CLI, the full API, iMessage with RCS and SMS fallback, delivery webhooks |
| Pro | From $260 a month | Adds iMessage apps, payments, group messaging, zero data retention, managed load balancing and a dedicated Slack channel. Live location is a $79-a-month add-on. 7-day free trial, no card required |
| Enterprise | Custom | Volume discounts, contractual SLAs, forward-deployed engineers, SSO |
There’s no per-message charge on any plan. The pricing page doesn’t say whether the Pro price covers one line or several, so ask before you plan a fleet.
Two clauses in Linq’s terms matter if your product depends on it. Linq can suspend service without notice if a carrier or supplier requires it, and it can end the agreement “in Linq’s sole discretion, at any time and for any reason” by giving notice or revoking API access.
The rules that keep a Linq line healthy
Linq’s best practices read like a guide to not getting a number flagged. In short:
- Let people text first. Design for inbound-first messaging, and don’t use iMessage for cold outreach.
- Keep the first message plain. No links or media in your opening message.
- Share your contact card after you’ve sent at least one message, so your name shows up instead of a number.
- Get replies. Linq suggests getting three or more replies early and keeping about one inbound message for every two you send.
- Stay under about 7,000 messages a day per line. It isn’t enforced, but lines over it “do occasionally get flagged.”
- Don’t open about 50 or more new conversations on one line in 24 hours. That alone moves a line to “at risk.”
- Respect opt-outs. Linq blocks sends to anyone who texts STOP or a similar keyword, and you’re expected to catch softer “stop messaging me” requests yourself.
There’s also a burst limit of 30 messages a minute between any one sender and recipient. Each line carries a reputation of healthy, at risk or critical, and Linq tells you to pause outbound on a critical line until it recovers.
The upshot: Linq suits an assistant that people choose to text. If you need to reach strangers in volume, it’s the wrong tool, and Linq says so itself.
Linq’s reliability record
Linq advertises 99.95% uptime and latency under 120 milliseconds. Its public status page gives a fuller picture. Between April 23 and November 11, 2026, it logged 21 incidents: 14 minor, 4 major and 3 critical. Most were resolved within about two hours, and several were posted after they’d already been fixed.
A few stand out:
- May 19: a two-to-three-minute outage at the API gateway.
- May 20: “a grid level power failure at one of our datacenters” took a subset of lines down for about two hours.
- June 30: an API incident lasting about an hour, the same day as a separate slowdown.
- November 10 (US time): when Apple reported disruptions to iCloud and Sign in with Apple, Linq saw contact card errors, send timeouts and “iMessage sending failures affecting some customers” until Apple’s services recovered.
That last one is a reminder of what you’re buying. Linq’s uptime depends partly on Apple’s, and its terms say as much: messaging “relies on third-party platforms… (including, without limitation, Apple),” whose limits “may change at any time, with or without notice.” The pricing page lists contractual SLAs under Enterprise, so if uptime guarantees matter, get them in writing.
Security and the Apple question
Linq calls itself “the only SOC 2 Type II iMessage API,” though other providers, including Photon, make the same certification claim. Ask for the current report either way. Linq publishes its control list and subprocessors on its security page.
Linq also says customer data is “encrypted and inaccessible to Linq.” It’s worth asking how that works in practice, since Linq’s systems deliver every message’s content to your webhook. Pro includes zero data retention, and Linq offers ephemeral messaging, which deletes message content after a window of 60 minutes to 24 hours that support sets for your account.
The larger risk is Apple. Apple’s official business channel is Apple Messages for Business, where customers start conversations through approved providers. Services like Linq run outside that program. TechCrunch put the open question plainly: “There’s no telling if Apple will pull a Meta and bar third parties from offering AI chatbots on its platform.” Potter’s answer is to expand beyond iMessage. He told TechCrunch the goal is Slack, email, Telegram, WhatsApp, Discord and Signal too, though the API today covers iMessage, RCS, SMS and voice.
Linq compared with other iMessage APIs
| Linq | Blooio | Photon | |
|---|---|---|---|
| Main audience | AI agent and consumer app builders | Small businesses, agencies and AI agents | Developers and early-stage startups |
| Reaching new people | Not for cold outreach; about 50 new chats a day per line before it’s at risk | Cold outreach prohibited; dedicated lines paced by reply rate | Business plan: up to 50 new contacts a day per line |
| Free option | Hobby, 20 contacts | 20-message trial | Self-host, or 10 users hosted |
| Other channels | Voice | Apple Messages for Business, RCS business messaging, SMS and voice | WhatsApp, Telegram, voice |
| Open source | No | No | Yes |
Other providers include Sendblue, Chert, messages.dev and ZeroSettle, which sell similar managed lines, and BlueBubbles, which is free if you run your own Mac as the server. Twilio and other SMS providers don’t offer iMessage at all.
Who should use Linq
Linq is a strong fit if:
- You’re building an assistant or consumer app that people text, and iMessage is central to the product.
- You want managed load balancing across a pool of lines, without handling reputation and failover yourself.
- You need payments, group chats or iMessage apps inside the conversation.
Look elsewhere if:
- Your plan depends on outbound sales or reaching people who haven’t heard of you. Linq’s rules are built against it.
- You can’t accept a vendor that can end the contract at its discretion with notice.
- Your users are mostly outside the US, where iMessage matters less than WhatsApp or Telegram.
And if you’re not building an agent product at all, but want your own business to have one that answers the phone and handles texts, you don’t need an API. Carly does that out of the box: you add it to ChatGPT or Claude, get a business number, and its agents answer calls, text back missed callers and reply on WhatsApp. It sends standard SMS, not iMessage. Our guides to AI text messaging and business texting cover that route.
FAQ
Is Linq still a digital business card company?
Not mainly. Linq still sells digital business cards on its site, but since 2025 the company has focused on its messaging API for AI agents and apps.
Who founded Linq?
Elliott Potter (CEO), Patrick Sullivan (CTO) and Jared Mattsson (president), who all worked at Shipt. The company is based in Birmingham, Alabama.
How much does Linq cost?
There’s a free Hobby plan for up to 20 contacts. Pro starts at $260 a month with a 7-day free trial, and Enterprise pricing is custom. Linq doesn’t charge per message.
Can I use Linq for sales outreach?
Linq’s docs say not to use iMessage for cold outreach, and opening about 50 or more new conversations on a line in a day puts it at risk. Its terms also require consent from every recipient.
Does Linq work with Android phones?
Yes. When the recipient can’t receive iMessage, Linq falls back to RCS or SMS.
Which apps use Linq?
Linq’s site features Poke, Tomo, Lindy, Soar, Arden and Orchid, and its guidance names Clay, Emergent, Slash and Owner.com as customers.
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