SMS for apps.

Integrate our SMS API into your app's backend. Your server sends HTTPS requests to our API endpoint with the recipient's number, your message, and your API key. We handle the delivery to mobile networks. This works with any tech stack: iOS (Swift), Android (Kotlin/Java), React Native, Flutter, or any server-side framework. The integration typically takes less than an hour with our code samples. See how Blink OMS integrated SMS into their healthcare platform.

SMS 2FA significantly improves security compared to password-only authentication. While no single method is 100% secure, SMS-based verification is recommended by NIST as an acceptable second factor and is used by over 80% of businesses for identity verification (Statista). It works on every phone without requiring a separate authenticator app, making it the most accessible form of 2FA available. For most applications, SMS 2FA provides the right balance of security and user convenience. Read our analysis of why SMS remains the gold standard for 2FA.

Verification codes are typically delivered within 1-3 seconds. Our API processes requests instantly and routes messages directly to UK mobile networks with no queuing and no batch processing. This speed is critical for 2FA codes where users are waiting in real time. With 98.5% delivery rates on direct network routes and sub-200ms API latency, your users receive codes almost immediately.

Yes, and it's one of the smartest reliability strategies for app notifications. Push notifications fail silently when the app isn't installed, notifications are disabled, the phone lacks internet, or battery saver is active. SMS bypasses all of these limitations. While push notifications achieve only 5-15% opt-in rates on many platforms, SMS reaches 100% of mobile phones without requiring app installation or notification permissions. Implement a fallback pattern: attempt push first, then send SMS if push delivery fails or isn't confirmed within your timeout window. This ensures critical messages always reach your users.

Our RESTful API works with any language that can make HTTPS requests, which is effectively every modern programming language. We provide ready-to-use code samples in cURL, PHP, Python, Node.js, Java, .NET/C#, and Ruby. Our documentation covers authentication, sending messages, receiving replies via webhooks, and checking delivery status. Most developers send their first message within 15 minutes.

Our API handles up to 600 messages per second with sub-200ms latency. For most applications, this is more than sufficient, and even high-traffic apps rarely need to send more than a few hundred messages per second. For enterprise-scale requirements, our SMPP integration offers sustained high-volume throughput with simultaneous delivery receipts. For non-API sending, our email-to-SMS service provides a no-code alternative. If you need capacity beyond standard API limits, contact us to discuss dedicated routing.

When you rent a reply number from us, inbound messages are forwarded to your application via webhooks. We send an HTTP POST to your configured endpoint with the sender's number, message content, and timestamp. Your app can then process the reply, whether that's confirming a booking, updating a record, or routing to your support system. This enables two-way conversational messaging within your application.

There are no setup fees, no monthly charges, and no minimum commitments. You pay only for messages sent, typically 3-7p per UK SMS depending on volume. We provide 25 free credits when you sign up so you can test the integration at no cost. For high-volume applications, we offer competitive volume pricing. See our volume pricing and credit rates for full details.