What does it mean when the connectivity icons in the status bar go white/gray? The connectivity icons (Data, Mobile Signal, Wifi) in the status bar on my Nexus S are normally green, but sometimes they go white. I can't seem to figure out what this means, as I still have a signal and can receive phonecalls/texts.

They are always all the same, e.g. either all white or all green. I'm on Android 2.3.4.
It has to do with whether or not you've currently got a good connection to Google's servers for sync services and the like. From page 27 of their Android 2.3 Users Guide:


  Network status icons turn green if you have a Google Account added to your phone
  and the phone is connected to Google services, for syncing your Gmail, Calendar
  events, contacts, for backing up your settings, and so on. If you don’t have a Google
  Account or if, for example, you’re connected to a Wi-Fi network that is not connected
  to the Internet, the network icons are white.


I'm not really sure why it bounces back and forth between green and white sometimes. I've noticed it on my phone but everything works fine (I run CyanogenMod, though, so perhaps it has to do with that). It could also be that green means it's currently in the act of syncing, but the wording in the document is a little vague, in my opinion.

In the case of Honeycomb or Ice Cream Sandwich, the colors are blue/grey instead of green/white, but they still have the same meaning.

Edit: For the interested, here are links to the user guide in other languages. The above is the English version.