I am coping with designing mobile apps, mostly iOS. I understood that for margin spacing I should go with 8, the smallest amount allowed, and follow with multiples of 8: 16, 24 etc.
By default I chose to go with 16px as the smallest amount for all the pages. Until I encountered a page with mostly text for which I believe that a 24px margin spacing looks better. Please see this example.
The first element, the header, is the default iOS header with small modifications.
The second element, the text box is..well a text box.
The last element is a call to action button.
My questions after scoring the internet, is there a golden rule on using different margin spacing in a single app? Second question, should that last element - being a call to action, a button - use the header's margin value (16px) or be consistent with the rest of the screen and use 24px?