httpSMS

About httpSMS

httpSMS is an open-source service that turns an Android phone into an SMS gateway, allowing SMS messages to be sent and received through an HTTP API. Requests are authenticated with an API key sent in the x-api-key header, and an Android app must be installed on the phone to trigger sending and receiving of messages. The API supports optional end-to-end encryption of message content.

The core send endpoint accepts a sender and recipient phone number and message content, and supports optional attachments (sent as MMS), a request ID for client-side tracking, and scheduled sending up to 20 days (480 hours) in advance. Responses include message metadata such as status, timestamps for sending and delivery, and failure reason. Webhooks are available for event notifications, and additional features include phone and API key management, control over SMS send rate, and an outgoing message queue.

The service provides code samples and official SDK client libraries for JavaScript and Go, along with examples for PHP, Python, curl, C#, and Java. It is intended for developers who want to integrate SMS sending and receiving capabilities into applications using an existing Android phone rather than a traditional SMS carrier API.

Key features

• Turns an Android phone into an SMS gateway controllable via HTTP API
• Send SMS and MMS messages (with attachments) via a REST API
• End-to-end encryption support for message content
• Schedule messages to send up to 20 days (480 hours) in the future
• Webhooks for SMS events
• Official JavaScript and Go SDK client libraries

Frequently asked questions