Chromium is switching to Aura UI. CEF on Windows is already using Aura, Linux will use Aura instead of GTK soon. You can read here on what is Aura. In short it's a non-native UI toolkit, the only native element is the toplevel window, everything inside is drawn by chrome.
CEF currently supports only Windows/Linux/OSX. CEF may support Android in the future but there is no schedule at this time. Try searching the CEF Forum for "android": http://www.magpcss.org/ceforum/search.php?keywords=android
For now, on Android you could use Chromview: https://github.com/pwnall/chromeview