SMS-TM
Our own SMS/OTP gateway: an Android phone with a SIM card instead of a provider
About the project
An ordinary Android phone with a local SIM card becomes a gateway: other services send verification codes and notifications through a REST API. The taxi app, ERP, discount card, marketplace and university system all run on SMS-TM.
What we did
- REST API: send SMS, send and verify OTP codes, webhooks
- Multiple phones with queue balancing and limits
- Device pairing by QR code from the web portal
- Runs 24/7 in the background and reconnects after network loss
- Separate client projects with their own keys, phones and logs
- Alerts about unsent SMS and SIM balance
Tech stack
- Node.js
- Express
- Socket.IO
- MySQL
- React
- TypeScript
- shadcn/ui
- Flutter
- Kotlin