Before the advent of the Force Touch trackpad on the 12" Macbook (and the new 13" Retina MacBook Pro), you could enable a gesture entitled Three Finger Drag. With that gesture, using three fingers you could touch the top bar of any window in OS X and drag the window around. I personally prefer it because click-dragging feels like it would help to wear out the trackpad clicker.
I guess with the advent of Force Touch which doesn’t have a mechanical clicker, Apple believes we don’t need easy access to this preference. Luckily, Apple does still believe in accessibility so that’s where they hid this feature.
On Non-Force Touch Systems – Open System Preferences
Select Trackpad
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Point & Click Tab
Select Three finger drag
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Not There On Force Touch Trackpad Systems
As you can see, there’s no three finger drag option
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Select Accessibility From System Preferences
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Select Mouse & Trackpad from the Left Sidebar
From this window choose Tracpad Options…
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Check the Box for Enable Dragging
And choose three finger drag from the pulldown menu.
Select OK and enjoy your three finger drag!
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