When developing 2D games it is common practice to reuse assets and animations when ever possible to keep the file size and memory consumption low. One of those practices has been flipping sprites using negative scale. With Unity 5.3 you now have the ability to quickly flip assets along the X and Y access in editor and code.
Getting Started with Flipping Sprites
Flipping sprites using the new flip property in the editor is made relatively simple, like other sprite level changes select your game object and under the sprite render component you will see a new property called flip with two options x and y. Simply Check the box and choose what type of flipping you want X, Y or both.
Just one of many in your arsenal of optimizing techniques, flipping sprites is a very welcomed and appreciated feature. The ease of quickly changing the direction of a sprite in the editor and by code is great. Now as great as it sounds this feature has one major limit; it only flips the render. So if you have colliders attached to your game object, that will not be flipped, in that case, you are still required to do negative scaling.