SMS & OTP Verification Integration
Phone-number login and transactional SMS that just work - with DLT registration for India, fallbacks and protection against OTP abuse.
What You Can Do With SMS & OTP
Phone number login
Passwordless sign-in with one-time passwords.
Two-factor authentication
An extra verification step for sensitive actions.
Transactional SMS
Order, booking and payment alerts.
Fallback channels
Retry over WhatsApp or voice when SMS is delayed.
What's Included
- Provider setup (Twilio, MSG91 or Firebase Phone Auth)
- DLT template registration guidance for India
- Rate limiting and OTP abuse protection
- Delivery tracking and fallbacks
Frequently Asked Questions
What is DLT registration?
In India, businesses must register their sender IDs and SMS templates on a DLT platform before sending commercial or transactional SMS. We guide you through it so messages are not blocked.
Which SMS provider should I use?
For India-focused apps, MSG91 or Firebase Phone Auth are cost-effective. For international reach, Twilio is a strong choice. We recommend based on your users and volumes.
How do you prevent OTP fraud?
We add rate limits, device and IP checks and CAPTCHA where needed, which protects against SMS pumping attacks that can run up large bills.
More Messaging Integrations
Need SMS & OTP in your app?
Tell us what you want to connect and we'll recommend the simplest, most reliable way to build it - with a clear timeline and fixed quote.