The Sharpen adjustment brings out finer detail in a photo and makes it pop out more.
Tap and turn on Sharpen.
Drag the Radius slider to control how much of an area around an edge should be sharpened. You can also tap the current value and enter a new value from 0 to 10 pixels.
Drag the Intensity slider to control how much the edges in the image should be sharpened. You can also manually enter a value from 0% to 100%.