When Google first showed off Android 4.0 Ice Cream Sandwich, everyone was seriously impressed by the massive facelift the OS received. It went from looking like a 90's shoe-in to something futuristic and fresh, and it brought about significant functionality changes as well. One of the things that made a lot of sense to a lot of people was the change of colors from black and green to black and "Holo Blue" as it was called, a color that feels very unique to Android. In the latest release of Android, 4.4 KitKat, Google has removed the Holo Blue color and replaced it with a light grey, opting for an even more minimalistic look than it had before. One of the biggest reasons for the color change was because Google wanted to go with transparent status bars, but the Holo Blue color just didn't show up well on most wallpapers, whereas the light grey does.
Google engineer Dan Sandler commented on an Android Police Google+ Post about the redesign and explained a few details on why this change was made:
1. Whiten ALL the status bar icons! Aesthetic concerns definitely factored into this (as has been mentioned elsewhere, a more neutral SystemUI allows apps to manage their own color palettes a bit better), but also keep in mind that with the new translucent bars feature, the color became a usability problem. Good old 33b5e5 doesn't pop as well on top of random wallpapers, even with the background protection.
Another thing that was changed in Android 4.4 KitKat was the removal of the icon color change when a data connection was established. In Android 4.0-4.3 when your phone connects to cell network data or a WiFi connection, the icon went from a grey to Holo Blue, indicating that a successful connection was established and you could get out to the Internet. Samsung was one of the first companies to do away with this, citing that users didn't like said functionality and that it was confusing. Apparently Google engineers decided to agree with Samsung here, as they not only changed the icons to grey as Samsung has had for some time now, but kept them grey even when there was a connection established. Instead of having the status bar icons change colors, the icons in the quick settings pull-down panel change, forcing you to go into quick settings if you want to see if your network connection is truly working. If you're wondering the icon will be orange in the quick settings panel if there is no data connectivity, and grey when there is connectivity.
Dan Sandler explains it like this:
2. What about the MCS GCM indicator? +Liam Spradlin basically called it: "Overall, network connectivity has been made strangely more opaque in KitKat, though for many average users this isn't a huge concern." In fact,most users find the colors confusing, if they notice them at all. Even the vanishingly small fraction of users who understood what the gray meant only really looked for it when things weren't working right; now you and I just have to remember to actually pop into quick settings to look for things like GCM liveness (orange is the new gray) and in/out indicators. Which brings me to...
Finally we come to icon animations. If you've updated your phone to an Android 4.4 KitKat based ROM or are lucky enough to be on a Nexus device that has KitKat already you might have noticed a complete lack of animations on any of the icons, even when data is clearly being pulled or pushed through a connection. This time around the design decision was more about performance and battery savings than any sort of aesthetic quality, and Dan Sandler once again explains how it drains the CPU and GPU cycles of a phone, even if minimally:
3. Bâ€”BUT MY BLINKENLIGHTS?! So this (the removal of the little in/out data traffic arrows from the RSSI) was mostly a performance consideration, believe it or not. The way the data bits are bubbled up and drawn was not only causing a ton of extra rendering work, but actually forcing a layout (!) in the status bar as well. We could have more aggressively cached the bitmaps (rather than creating new BitmapDrawables from resource IDs every time, which was causing the relayout) but that would still have left all the drawingâ€”multiple times per second in some casesâ€”sucking away precious CPU and GPU from your game or Launcher animations or whatever. In the end it seemed like a lot of work (and battery) for what was effectively visual noise, so this too was booted to Quick Settings where it would be available for us nerds.
If you don't care much for the change, well there's not a whole lot you can do about it if you like to stick with stock Android. It's likely that some ROM developers will give you the option to enable the old icons and behavior, but it seems that OEMs are content to keep it with the way they've had it, which is the same as the new AOSP stock Android behavior. Change is sometimes good and sometimes bad, but this one is definitely up to your own personal tastes. Let us know how you feel about it, we'd love to hear from you! Personally I'd rather have the information presented to me, and users who don't like it can just ignore it, but it's too late now.