I’m using Photoshop to make a 2D Pixel Character for my game in pixels that is Height: 28px and Width:19px, and I want to know what Resolution should I use.
For the size always make sure you use a 2x value, like:
2×2, 64×64, 1024×1024 etc.
2×4, 512×1024 etc.
And for the resolution use:
72 Pixels/Inch (standard for screens)
It is always a good practice to set a default reference value for the height of one unit (1 Unity meter, like: 32px = 1Unit or 16px = 1Unit. This for scale and keeping things the same. Also when you comeback in Unity your Pixel Per Unit import setting will be this value.)