Answer:
A dagger thrust at my own heart, dictates the way I'm swayed. Left I stand, and right I yield, to the twisting of the blade.
What does a WW1 Trench, A Submarine and a Popular Phone App all have in common?
What's black when you get it, red when you use it, and white when you're all through with it?
Tool of thief, toy of queen. Always used to be unseen. Sign of joy, sign of sorrow. Giving all likeness borrowed.
I pass before the sun, but make no shadow.
Both old people and owls are said to be possessing this trait
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?