If you prefer to visually see if you have a message like iMessage or from Whatsapp, you can enable this feature in the Settings. This won’t mimic the same way as BlackBerry constant LED Flash when you don’t read the message right away, this feature is ON only when you receive the message right there and there. It won’t stay on until you dismiss it, which kind of defeat the purpose to let you know you have a message waiting. But it’s still better visually so you don’t rely on vibrate or sound to get your attention. LED Flash is another way to get your attention. This only works on the iPhone only and on iOS 5 and above. To enable LED Flash when message is received…
To enable you have to go to Settings > General > Accessibility > and Scroll Down to LED Flash and slide to ON.
That’s it to set it up.
So far it works with Whatsapp, Viber and Skype. Even when there is a call it will Flash. It gets annoying at night though if you have it out of your pocket. It will flash bright and will eventually drain your battery faster than not.
You have to remember that this feature is under disability, for handicap purposes. I use at work when my eyes is off the phone and on my computer, when a message comes through, I can see the flash from the corner of my eyes. I have my iPhone with the screen down to see the bright flash. I have my headphones on when I work, so I won’t be able to hear the sound or feel the vibration. So the Flash LED is a good backup in-case I miss a message or when an incoming call is coming through, the LED Flash will get my attention. So far it has not failed me.