Apple - Snap feature for Mac?

For window arranging:

• SizeUp $13
• Divvy $14
• Breeze $8
• ShiftIt Free
• Mercury Mover $20
• Optimal Layout $14
• Cinch $7
• Moom $10

Spectacle was mentioned in a question that was marked as duplicate of this one, but has not yet appeared here. It is also open source:

• Spectacle at Github

Also, OS X El Capitan (OS X 10.11) will have a side-to-side snap feature when it is released later in 2015 using Mission Control.

You may also be looking for SizeUp (13$). That emulates the Windows Snap features better, I think.