If you look at your iPhone when its face-down you’ll notice that the camera and the flash face “up.” Fortunately, Apple thought through how to use the flash to alert the user when a message has been received. You’ll find this brilliant feature under Settings > General > Accessibility. Scroll down to “LED Flash for Alerts” and turn it “on.” The camera flash will now blink when a message comes through but no where near as bright as when the flash is used while taking a photo.
“Perhaps the most ‘pro of tips’ for the iPhone.”
Thorough down to the last detail.