A one-time password (OTP) is a temporary, single-use code sent to a user's phone via SMS to verify their identity. Unlike static passwords, OTPs expire after a short period and cannot be reused, making them a powerful tool against unauthorized access, phishing, and credential theft.
With SmsGateWay24, you can integrate OTP delivery into any application using your own Android phone and SIM card — no expensive SMS provider contracts required.
Your backend application generates a random numeric or alphanumeric code (typically 4–8 digits). This code is stored temporarily in your database with a timestamp and linked to the user's account or session.
Your application calls the SmsGateWay24 API with the recipient's phone number and the OTP message text. The API request is simple:
POST /api/v1/send
{
"phone": "+1234567890",
"message": "Your verification code: 847291. Valid for 5 minutes.",
"device_id": "your_device_id"
}
The SmsGateWay24 app on your Android device receives the task and sends the SMS immediately through your SIM card.
The user receives the SMS and enters the OTP into your application. Your backend verifies the code against the stored value and checks that it has not expired. If valid, the user is authenticated or the transaction is confirmed.
OTPs should expire within 3–10 minutes. Longer validity windows increase the risk of interception or replay attacks. Display the expiry time in the SMS message so users know how long they have.
Implement a maximum number of failed attempts (e.g., 5) before locking the session. This prevents brute-force attacks where an attacker tries all possible combinations.
Always transmit OTPs and API credentials over encrypted connections. Never send OTP values in URL query parameters where they may be logged by proxies or browsers.
Once the OTP has been successfully verified, immediately mark it as used in your database. A valid OTP should only work once.
Commercial SMS providers charge per message, which becomes expensive at scale. With SmsGateWay24, you use your existing SIM card plan — local messages cost only what your mobile operator charges, often a fraction of a cent. For businesses sending hundreds or thousands of OTPs per day, this can represent significant savings.
Additionally, local SIM cards often achieve higher delivery rates than international SMS routes used by global providers, especially in countries with strict telecom regulations.
Service messages are automated SMS notifications sent to customers or users informing them about important events related to their orders, subscriptions, deliveries, or account activity. Unlike promotional messages, service messages are transactional — they are triggered by a specific event and expected by the recipient.
Examples include: order confirmation, shipping notification, delivery update, appointment reminder, payment receipt, and account security alert. With SmsGateWay24, you can automate the sending of all these messages through your own Android phone and SIM card.
Automatically notify customers when their order has been placed, processed, shipped, and delivered. Each status change triggers an SMS, keeping the customer informed without any manual effort on your side. This reduces support inquiries and increases customer satisfaction.
Reduce no-shows by sending automated SMS reminders 24 hours and 1 hour before a scheduled appointment. Include the time, location, and a link to reschedule if needed.
Notify customers when a payment is received, when an invoice is due, or when a subscription is about to renew. This improves cash flow and reduces overdue accounts.
Alert users about login activity from new devices, password changes, or suspicious account actions. These messages build trust and allow users to react quickly to potential threats.
Install the SmsGateWay24 app on an Android phone with an active SIM card. Register the device in your account dashboard. The device will appear online and ready to send messages.
Use the SmsGateWay24 REST API to send messages from your backend system. Generate an API token in the dashboard and include it in your requests. The API supports JSON payloads and responds with delivery status information.
Configure a webhook URL in your SmsGateWay24 account. When a message is delivered (or fails), SmsGateWay24 will send a POST request to your server with the delivery status. This allows you to track every message and take action on failures.
Using a local SIM card through SmsGateWay24 provides several advantages over commercial SMS gateways: lower cost per message, better delivery rates for local numbers, no dependency on third-party providers, and full control over message content and timing.
System monitoring is the practice of continuously observing the state of your infrastructure — servers, databases, services, and network devices — and reacting quickly when something goes wrong. While email and app notifications are common, SMS alerts delivered directly to a phone offer an important advantage: they are seen immediately, even when the recipient is away from a computer or has poor internet access.
With SmsGateWay24, you can configure your monitoring tools to send SMS alerts through your Android phone's SIM card, without relying on expensive commercial SMS gateways.
Monitor uptime for your web servers, application servers, and APIs. When a service goes down, an SMS is sent immediately to the on-call engineer. This is critical for reducing mean time to resolution (MTTR) — the sooner the team is notified, the sooner the issue is fixed.
Set thresholds for CPU usage, RAM consumption, and disk space. When usage exceeds the defined limit (e.g., disk at 90%), an SMS alert is triggered. This prevents outages caused by resource exhaustion before they happen.
Integrate SmsGateWay24 with your logging system (e.g., Grafana, Zabbix, Nagios, or a custom script) to send an SMS when error rates spike above a normal baseline. This allows teams to catch application regressions quickly after deployments.
Alert on slow queries, replication lag, connection pool exhaustion, or failed backups. Database issues can cascade quickly, and SMS alerts ensure the DBA is notified even outside of working hours.
Detect and alert on unusual network traffic patterns, failed login attempts, firewall rule violations, or SSL certificate expiration. Early notification gives security teams time to respond before a minor incident becomes a breach.
SmsGateWay24 provides a simple REST API that any monitoring tool or custom script can call. A typical alert script looks like this:
curl -X POST https://smsgateway24.com/api/v1/send -H "Authorization: Bearer YOUR_TOKEN" -d "phone=+1234567890&message=ALERT: CPU at 95% on server-01&device_id=YOUR_DEVICE"
In Zabbix, create a new media type of type "Script" or "Webhook" that calls the SmsGateWay24 API. Assign it to the appropriate user and link it to your alert actions. Zabbix will then automatically send SMS whenever a trigger fires.
Use Grafana's alerting webhook feature. Configure a notification channel with a webhook URL pointing to a small middleware script that forwards the Grafana payload to the SmsGateWay24 API.
For lightweight setups, a simple shell script run by cron every minute can check a condition (e.g., disk usage) and call the API if the threshold is exceeded. This requires no additional monitoring software.
GPS tracking systems monitor the real-time location of vehicles, assets, or personnel using GPS receivers installed on the tracked object. The GPS device records coordinates and, at regular intervals or when triggered by an event (such as speeding or entering a geofence), transmits this data to a central server.
SMS is one of the most reliable transmission channels for GPS data, especially in areas with limited internet connectivity. SmsGateWay24 allows you to receive and process these location updates through your Android phone, providing a low-cost, reliable tracking infrastructure.
Track the location of delivery vehicles, trucks, or company cars in real time. Receive SMS updates when a vehicle leaves a designated zone, exceeds the speed limit, or completes a delivery. This improves driver accountability and reduces unauthorized vehicle use.
Monitor the location of valuable equipment, trailers, or containers. GPS trackers with SIM cards can send periodic SMS updates with coordinates, which your server receives via SmsGateWay24 and stores in your database.
Field workers in remote areas can use SMS-based GPS trackers to send their location to a central dispatch system. This is especially useful in areas with limited mobile internet where SMS is more reliable than data connections.
Configure your GPS tracker to send an SMS alert when it enters or exits a defined geographic area (geofence). SmsGateWay24 receives the incoming SMS and forwards it to your server via webhook, triggering automated responses like sending a notification email or updating a map.
Program your GPS tracker device to send SMS messages with coordinates to the phone number of the SIM card installed in your SmsGateWay24 Android device. Most GPS trackers support SMS commands for configuration.
In your SmsGateWay24 account, configure an incoming SMS webhook. When the GPS tracker sends a location update SMS, SmsGateWay24 receives it and immediately POSTs the message content to your server's webhook URL.
Your server receives the webhook payload containing the SMS text with GPS coordinates. Parse the coordinates from the message format used by your specific GPS tracker model. Store them in your database and display them on a map.
Optionally, configure your server to respond to certain GPS events. For example, if a tracker sends a geofence violation alert, your server can automatically send an SMS back through SmsGateWay24 API with instructions or acknowledgment.