You cannot change the font size in PivotItem. Instead, you can create a template in which you can add a TextBlock and consider it a title. Please find a sample here.
<controls:Pivot Title="whatever" Name="pivot"> <controls:PivotItem Margin="11,28,13,0" > <controls:PivotItem.Header> <Grid> <TextBlock Name="FirstPivot" FontSize="31" Text="FirstPivot" /> </Grid> </controls:PivotItem.Header> <Grid> </Grid> </controls:Pivot>
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