How to remove UIButton selected background color?

I had this same issue and I resolve it by changing the UIButton type from "System" to "Custom". The blue background color does not show up in selected state when it is a "Custom" type.

Unfortunately I'm away from my test machine at the moment, but there are two things you could try.

First would be to set the following property:

button.adjustsImageWhenHighlighted = NO;

Or uncheck "Highlight adjusts image" in Interface Builder.

If that doesn't work like you expect it to, you can deselect the button in the action you tied it to, like so:

- (IBAction)yourButtonAction:(id)sender {
    [sender setHighlighted:NO];
}

Change the alpha of the tintColor to zero, works if iOS is 5.0 or later

UIColor *color = [[UIColor alloc] initWithRed:0.0 green:0.0 blue:0.0 alpha:0.0];  
button.tintColor = color;

Very simple, in storyBoard, select your UIButton and open attribute inspector. Now scroll down to View section and change Tint property to Clear Color or any specific color if u want.