To add a watermark to photos at the moment you capture them, you can use a camera app that supports real-time watermarking. Here are the general steps:
1. Install a camera app with real-time watermarking capability, such as "Camera MX" or "Open Camera."
2. Open the camera app and access the settings or options menu.
3. Look for the watermarking or stamp feature and enable it.
4. Customize the watermark by adding text, logo, or graphic elements.
5. Adjust the position, size, transparency, and other settings as desired.
6. Capture photos using the camera app, and the watermark will be added automatically.
Remember to explore the specific features and settings of the camera app you choose for more detailed instructions on adding watermarks in real-time.