Developer Tools

Relayion

Turn any Android phone into an SMS gateway — send and receive messages via a simple API, flat monthly rate.

relayion.com

Verified API available Works with n8n Free tier

Quick facts
What is it	Turn any Android phone into an SMS gateway — send and receive messages via a simple API, flat monthly rate.
Pricing	Freemium — from $9.9/mo
Free tier	Yes
Platform	Web Application
API	Yes
Works with	n8n
Best for	sending appointment reminders from a clinic's own number, delivering OTPs and 2FA codes via a real SIM
Domain registered	2026

Data updated Sept. 19, 2026

What does Relayion do?

Relayion is an SMS gateway API that turns any Android phone into a messaging endpoint. Instead of signing up for a third-party SMS provider, you install the Relayion app on an Android device, connect it to your account, and send messages through your own SIM card. The API is straightforward — a single POST request to /api/v1/outbound with a recipient number and message body dispatches the SMS from your phone via the carrier network. There's no per-message pricing; you pay a flat monthly rate.

Setting up Relayion takes minutes. Install the Android app, generate a pairing code in the Relayion Console, and enter it in the app. No USB cables or carrier paperwork. Each integration gets its own API key, which you can scope to a specific device or SIM slot and rotate without downtime. The app runs as a foreground service and stays connected to Relayion's cloud, so messages queue and dispatch reliably even if the phone reboots. Multi-SIM fallback is available for critical messages like OTPs.

Relayion is for developers and businesses that want full control over their SMS infrastructure. Use cases include clinic appointment reminders from a familiar local number, two-factor authentication codes sent through a real SIM, and order updates that customers trust because they come from a known number. AI agents can also send and receive texts through the same API. The free plan includes one device and 500 messages per month with no credit card required.

Developer Tools Non-AI Communication — Other

Key features

What makes it stand out

Connect an Android phone as a sending device with a background-running app

Link devices to your account with a pairing code — no USB or carrier paperwork

Integrate with one API key per application, scoped to device or SIM slot

Send messages via a single POST request and receive replies through webhooks

Flat monthly pricing, not per-message fees

Who is Relayion for?

Who benefits most from this tool

sending appointment reminders from a clinic's own number

delivering OTPs and 2FA codes via a real SIM

sending order and shipping updates from a familiar local number

Pricing

Free tier available — start without a credit card

Free

1 Devices
500 / month Monthly cap
5 msgs concurrent Burst Capacity
Up to 1 / min Sustained Rate
Outbound SMS
Inbound SMS + webhooks
Multi-SIM targeting
Best-effort support

Starter

$9.90/month

Everything in Free, plus:

3 Devices
No cap Monthly cap
50 msgs concurrent Burst Capacity
Up to 20 / min Sustained Rate
5 webhook retries
Email support

Pro

$29.90/month

Everything in Starter, plus:

10 Devices
No cap Monthly cap
100 msgs concurrent Burst Capacity
Up to 50 / min Sustained Rate
10 webhook retries
Priority email support

Enterprise

Custom

Everything in Pro, plus:

Custom device count
Custom burst capacity & sustained rates
Custom SLA terms
MSA / custom contract
Dedicated onboarding + account manager
Dedicated support

Trust & presence

Domain Domain registered 2026

Gallery

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