i have activities which i themed with my custom theme, but for spinner i choosed to style it with Appcompat v21 but i got this :
There is a way to change your arrow color... actually it's not color you can change this image with blue color image..
create a xml file myspinner_selector
in your drawable folder
and paste
// you can use any other image here, instead of default_holo_dark_am
blue_arrow is an image, and add this style in your style file
finally add this style in your spinner
it look like this. you need to customize