SMSTunnel Android App

Why Use SMSTunnel?

Traditional SMS gateways charge per message and require complex setup. SMSTunnel is different - it uses your existing Android phone to send messages, which means:

• No per-message fees - Use your unlimited SMS plan or pay carrier rates
• Your phone number - Recipients see your real number, not a random shortcode
• Instant setup - Install the app, scan a QR code, and you're ready
• Full control - Your messages, your data, your infrastructure

Key Features

🌍 Country Restrictions

Control exactly which countries you can send SMS to. Prevent accidental (or malicious) international messages that could result in high charges:

• Single Country Mode - Restrict sending to only your home country
• Allowed Countries List - Create a whitelist of permitted destination countries
• Auto-detection - Automatically detects and validates phone number country codes

⚡ Rate Limiting

Protect your carrier relationship and avoid being flagged as spam. Configure sending rates to match your mobile operator's acceptable limits:

• Messages per minute - Set maximum SMS sent per minute (e.g., 10/min)
• Messages per hour - Hourly limits for sustained sending
• Daily limits - Maximum messages per day for extra protection
• Queue management - Messages are queued and sent at configured rate

🚫 Number Blocking

Automatic protection against expensive or problematic destinations:

• Premium rate numbers - Blocks sending to premium/paid services (090x, etc.)
• Special service numbers - Blocks emergency and special service numbers
• Satellite phones - Blocks extremely expensive satellite numbers (+881, +882)
• Shortcodes - Blocks messages to SMS shortcodes
• Custom blocklist - Add your own numbers or patterns to block

🔐 Security Features

• Biometric login - Protect the app with fingerprint or face unlock
• E2E Encryption - Optional end-to-end encryption for sensitive messages
• Secure connection - TLS encrypted connection to SMSTunnel servers
• No message storage - Messages are not stored on our servers

📊 Monitoring & Analytics

• Real-time status - See delivery status of each message
• Message history - Browse sent and received messages
• Usage statistics - Track daily, weekly, and monthly usage
• Delivery reports - Know when messages are delivered

🔄 Background Operation

• Always-on service - Runs reliably in background
• Battery optimized - Minimal battery impact with smart wake locks
• Auto-reconnect - Automatically reconnects after network changes
• Boot start - Optionally start automatically when phone boots

Screenshots

How It Works

1. Install the app on your Android phone
2. Create an account or sign in with Google
3. Connect to your dashboard by scanning the QR code
4. Configure settings - country restrictions, rate limits, etc.
5. Start sending from your website, app, or API

When your application sends an SMS via the SMSTunnel API, the message is securely transmitted to your phone, which then sends it as a regular SMS using your carrier. Recipients see your phone number and can reply directly to you.

Settings Reference

Country Settings

Rate Limit Settings

Blocking Settings

Requirements

• Android 8.0 (Oreo) or higher
• SMS permissions granted
• Internet connection (WiFi or mobile data)
• Background battery optimization disabled (for reliable operation)
• SMSTunnel account (free tier available)

Permissions Explained

• SEND_SMS - Required to send SMS messages
• RECEIVE_SMS - Required to receive SMS and forward to dashboard
• READ_SMS - Required to track delivery status
• READ_PHONE_STATE - Required to detect SIM and carrier info
• INTERNET - Required to connect to SMSTunnel servers
• FOREGROUND_SERVICE - Required to run reliably in background
• CAMERA - Optional, for QR code scanning
• BIOMETRIC - Optional, for secure app access

FAQ

Will this drain my battery?

The app is optimized for minimal battery usage. It maintains a persistent connection using WebSocket, which is very efficient. Most users report less than 3% additional battery usage per day.

What if I lose internet connection?

Messages are queued until connection is restored. The app automatically reconnects when internet becomes available.

Can I use multiple phones?

Yes! You can connect multiple Android phones to your SMSTunnel account. Messages can be load-balanced across devices or you can set a default device.

Is my data safe?

Messages are transmitted over encrypted TLS connections. With E2E encryption enabled, even we cannot read your message content. Messages are never stored on our servers beyond the delivery window.

Changelog

Version 1.0.0

• Initial release
• QR code pairing
• Google and email authentication
• Country restrictions
• Rate limiting
• Number blocking
• E2E encryption support
• Biometric authentication
• Background service