Little arrow on Wi-Fi icon on system tray

[Bruno Blanes]

I would like to know what does that arrow mean and when does it show up as I'm on WP8.1 Update 1 and have never seen it.

F.Y.I.: That arrow is on every image of phones posted on WPCentral news articles. If you don't know about it, check it out...

 

[David P2]

That's normal behaviour. Just signifies incoming/outgoing data.

 

[Bruno Blanes]

Thought so, but why isn't it show for me and since when does it shows up?

 

[David P2]

It comes with the Cyan firmware, but I don't think all devices get it for some reason. My 620 did though.