Two-Way SMS & Inbound Webhooks
Transform SMS into an engaging bidirectional dialogue. Receive customer responses, survey answers, and confirmation replies back into your application via secure HTTP webhooks, complete with signature verification and replay protection.
Service features
Real-time HTTP POST webhooks for inbound customer messages and keyword replies
Cryptographic HMAC signature validation for secure webhook authenticity
Automated webhook retry policy with exponential backoff
Integrate with CRM platforms, Zendesk, Slack, or custom internal backends
Detailed event logs and webhook testing replay console
API integration
Send SMS programmatically with standard JSON requests. Pass your authorized API key, target recipient numbers, and receive instant synchronous delivery receipts with carrier timestamps.
curl -X POST https://sms.allotropicltd.com/api/public/v1/sms/send \
-H "Authorization: Bearer alt_live_your_key" \
-H "Content-Type: application/json" \
-H "Idempotency-Key: two-way-sms-webhooks-001" \
-d '{
"sender_id": "MYBRAND",
"to": "255712345678",
"message": "Hello from Allotropic Two-Way SMS & Inbound Webhooks"
}'Frequently Asked Questions
Common questions about Two-Way SMS & Inbound Webhooks in Tanzania & East Africa.
How do I secure my webhook endpoint?
Allotropic signs webhook payloads with a unique secret key using HMAC SHA-256, allowing you to verify that events genuinely originate from our platform.
What happens if my server is temporarily offline when a webhook is sent?
Our webhook system retries failed deliveries using exponential backoff over a 24-hour period.
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