After changing the user avatar on github it is not refreshed in the Android client. I did change the avatar couple weeks ago.
I can confirm this. Android 4.1.1, app version 1.6.1.
Wiping the application cache refreshed it by the way.
Well I guess that helps because the app fills the cache again ;)
I confirm the above issue. When I reinstalled the app, my fresh avatar showed up! Before this it was the default git logo that appeared.