[AC Question]

I did a system update this morning and afterwards all the background and text colors changed. Contacts area is green with white, other ones are orange and white and the icons for apps got bigger to. Can we undo what ever the update did?

[B. Diddy]

Welcome to Android Central! Which phone? I assume you got Lollipop--that's part of Material Design. To undo the update, you'd have to flash back to KitKat (which might require rooting, or using Odin if it's Samsung). Or you could try installing an alternative launcher like Nova or Apex.