How do you view a large mp4 email attachment on the iPhone?

To view a large MP4 email attachment on an iphone, you can tap the attachment in the email to begin downloading it. If the file is too large, the iphone may prompt you to download it to your device or view it in a compatible app such as Apple Photos or Files. You can also consider saving the attachment to a cloud service like iCloud Drive or google Drive for easier access. Ensure you have a stable internet connection, especially for larger files.