Mystery Status Icon - What's this icon indicate?

Can anyone identify what status this status icon's indicating?

It's the rectangular icon between the Bluetooth logo and the battery strength percentage on the iPad. It doesn't always appear on the status bar. It also appears on the iPod Touch.

Have asked my local "experts" who have no idea. I know I've seen this icon on other devices in the past, but don't know what it is.

Thanks!

hoanganh said:

represented image of this one

Click to expand...

Excellent ... thank you all!