<Button Grid.Row="1" Grid.Column="1" Content="1" x:Name="btnMyButton" Click="btnMyButton_Click" FontSize="20" />

Tapped vs Click

Click – TOUCH OR KEYBOARD – Same as tapped plus can be triggered from keyboard input also if the button has focus.

Tapped – NOT KEYBOARD – triggered for a finger press, mouse button click, or pen tap

Any mouse button click raises a Tapped event.  A mouse left button click also raises a Click event.