You can use TabLayout.SetTabTextColors(NormalColor, SelectedColor)
for setting the tab text colors.
Using Text and Icon has the problem that icon and text will be displayed in one row and not with the text below the icon (at least that was the case when I last tried it. Maybe this is now changed in the support library?). To be totally free with the tabs you can create custom views for each tab. Unfortunately this is a bit complicated. See the TabsWithCustomViewExample2_0.zip of the DesignSupport library.