Follow these steps to write a pre-set text message to your NFC tag using the NFC Tools app.
Open the app and tap the Write button on the main dashboard.
Inside the Write menu, tap Add a record to view the list of available data types.
Scroll down and select SMS from the list. This is ideal for pet ID tags or luggage trackers.
Enter your phone number in the To field and your message (e.g., Hi! I found your pet!) in the Message field.
Tap the Checkmark in the top right to save the record.
Tap the orange Write / XX Bytes button. A "Ready to Scan" prompt will appear on your screen.
Hold the top of your phone near the NFC tag. Wait for the green checkmark to confirm the data has been written successfully.