string splashScreenName = "Default-Portrait@2x.png"; //you'll need to change this per device
string dataPath = Application.dataPath.Substring (0, Application.dataPath.Length - 4); //Remove "Data" from the end of the path
string imagePath = dataPath + splashScreenName;
UIImage image = new UIImage(imagePath);
Texture2D splashTexture = image.ToTexture2D();
Hi DuFF14, thanks for sharing this. One thing to be careful about using UIImage.ToTexture2D() is that it creates a new Texture2D, and the caller is responsible for destroying it once done, by calling Texture2D.destroy(splashTexture).
Alternatively, you can use Texture2D.LoadImage() passing in the bytes you get from the file.