It's the multicolored pinwheel icon on the Home Screen.;
, You should have several albums listed here, including "All Photos" and "Videos".


If you don't see any albums, tap Albums in the bottom right corner of the screen.
, It's on the bottom of the screen, to the left of the garbage can icon.
 It's to the right of the three overlapping circles.
, It's below the Saturation option in the drop-down menu here.
 The slider at the bottom of the page controls the contrast between the colors in your photo. Dragging the slider right will decrease the contrast and dragging it left will increase the contrast.
 It's in the bottom right corner of the screen. Doing so will save your photo.
Open your iPhone's Photos.
Tap an album.
Select a photo to edit.

,
Tap the slider icon.
Tap the knob icon.
Tap the downward-facing arrow next to Color.

,
Tap Contrast.
Swipe the slider left or right.
Tap Done.
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