The easiest way is to customize the style for ActionBar, for example, as follows:
<resources>
<style name="MyTheme" parent="@android:style/Theme.Holo.Light">
<item name="android:actionBarStyle">@style/MyTheme.ActionBarStyle</item>
</style>
<style name="MyTheme.ActionBarStyle" parent="@android:style/Widget.Holo.Light.ActionBar">
<item name="android:titleTextStyle">@style/MyTheme.ActionBar.TitleTextStyle</item>
</style>
<style name="MyTheme.ActionBar.TitleTextStyle" parent="@android:style/TextAppearance.Holo.Widget.ActionBar.Title">
<item name="android:textColor">#f08080</item>
</style>
</resources>
Then apply this style on your page as follows:
[Activity(Label = "YOURPACKAGENAME", MainLauncher = true, Icon = "@drawable/icon", Theme = "@style/MyTheme")]
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